50 câu hỏi
Mark the letter A, B, C or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions
stopped
decided
worked
washed
Mark the letter A, B, C or D on your answer sheet to indicate the word whose underlined part differs from the other three in pronunciation in each of the following questions
valentine
discipline
determine
imagine
Mark the letter A, B, C or D on your answer sheet to indicate the word that differs from the other three in the position of primary stress in each of the following questions
promote
profess
product
provide
Mark the letter A, B, C or D on your answer sheet to indicate the word that differs from the other three in the position of primary stress in each of the following questions
property
regular
different
achieving
I’d prefer to do it on myself, because other people make me nervous
I’d prefer
on myself
other
make
The continental shelves in the shallow area of the ocean floor is closet to the continents.
shelves
of
ocean floor
closet to
The average adult get two to five colds each year
The
get
to
colds
Since our train leaves at 10.30, it is _______that everyone be at the station no later than 10.15
urgent
inescapable
desired
imperative
Insects and bugs ____________.
make my skin march
make my skin turn
make my skin crawl
make my skin walk
Mrs. Robinson _______ great pride in her cooking
has
finds
gets
takes
The fastest runner took the ___________ just five metres before the finishing line
advance
lead
place
head
The teacher as well as his students____________ at the school meeting yet
arrived
hasn’t arrived
haven’t arrived
not arriving
If I had been absent from class yesterday, I___ the math test
would miss
would have missed
will miss
miss
Tennis fans _____ tickets have been queuing all night at Wimbledon
who are hoped to buy
whom hoped to buy
hoping to buy
hoped to buy
We’re free most of the weekend, but we’ve got a few bits and ______to do on Sunday morning
stuff
ends
things
pieces
Ann pretended ______ me as he passed me in the street
not seeing
not to seen
not see
not to see
My daughter plays _____ piano very well
the
X
X
an
In this course, students receive _______ in the basic English grammar
instruct
instructional
instruction
instructive
In the early years of the 20th century, several rebellions broke_____in the northern parts of the country.
down
up
out
into
I have just bought a television set _ _ in Japan
which made
in which made
who is made
made
she got the salary last week, she has complained that she is out of money
Unless
Even though
In case
As
Marcelo: "Reese, make us some tea, would you?" - Reese: "_____________."
Go on. Make yourself at home
No, I won't, I'm afraid
Sorry, I am not
I'm afraid I can't
Esme: "Do you have a minute?" - Kailyn: "_____________."
Well, that makes sense
Yes, but please be brief
That's just great. Thanks
Sorry, I left my watch home
Mark the letter A, B, C or D on your answer sheet to indicate the word(s) CLOSEST in meaning to the underlined word(s) in each of the following questions
Our team must develop a new strategy in order to deal with the serious problem
expand
grow
arise
invent
Several hypotheses for global warming have been suggested by the scientists
supposition
study
research
truth
Mark the letter A, B, C or D on your answer sheet to indicate the word(s) OPPOSITE in meaning to the underlined word(s) in each of the following questions
The band had an outstanding performance at the Grand Theatre last night
good
excellent
gentle
bad
The writer was really hot under the collar when his novel was mistaken for another
angry
worried
calm
curious
Bill drives more carelessly than he used to
Bill doesn’t drive as carefully as he used to
Bill doesn’t more drive carefully than he used to
Bill doesn’t drive as carefully he used to
Bill doesn’t drive as carefully as he used
“What were you doing last night, Mr John?” asked the police
The police asked what were you doing last night, Mr John
The police asked Mr John what he had been doing the night before
The police asked Mr John what he had been done the night beforev
The police asked Mr John what had he been done the night before
It wasn’t necessary for you to do all this work
You mustn’t have done all this work
You couldn’t have done all this work.
You couldn’t have done all this work.
You needn’t have done all this work
He started computer programming as soon as he left school
No sooner had he started computer programming than he left school
Hardly had he started computer programming when he left school
No sooner had he left school than he started computer programming
After he left school, he had started computer programming
Susan did not buy that villa. She now regrets it.
Susan wishes she had bought that villa
Susan regrets having bought that villa
If only Susan didn’t buy that villa
Susan wished she hadn’t bought that villa
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 33 to 37.
When you first arrive in a foreign culture, often your first reaction is completely positive. Everything seems exciting, different and fascinating. It’s an (33)______. If you are just on a short holiday, you will probably never leave this phase.
(34)_______, if you stay longer, your attitude can start to change. As you start to realize (35)_____ little you really understand the new culture, life can get frustrating. People misunderstand what you are trying to say, or they may laugh at you when you say something incorrectly. Even simple things, like posting a letter, can seem very difficult to you. Thus, you are likely to get angry or upset when things go wrong.
With time, though, you start to (36)______ to become more comfortable with the differences and better able to handle frustrating situations. Your (37)______ of humor reappears. Finally, you may feel enthusiastic about the culture once again, enjoy living in it, and even prefer certain aspects of the culture to your own.
(Adapted from Navigate – Coursebook, OUP 2015)
Điền ô 33
adventure
adventurous
adventurer
adventurously
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 33 to 37.
When you first arrive in a foreign culture, often your first reaction is completely positive. Everything seems exciting, different and fascinating. It’s an (33)______. If you are just on a short holiday, you will probably never leave this phase.
(34)_______, if you stay longer, your attitude can start to change. As you start to realize (35)_____ little you really understand the new culture, life can get frustrating. People misunderstand what you are trying to say, or they may laugh at you when you say something incorrectly. Even simple things, like posting a letter, can seem very difficult to you. Thus, you are likely to get angry or upset when things go wrong.
With time, though, you start to (36)______ to become more comfortable with the differences and better able to handle frustrating situations. Your (37)______ of humor reappears. Finally, you may feel enthusiastic about the culture once again, enjoy living in it, and even prefer certain aspects of the culture to your own.
(Adapted from Navigate – Coursebook, OUP 2015)
Điền ô 34
Therefore
Or
However
Nor
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 33 to 37.
When you first arrive in a foreign culture, often your first reaction is completely positive. Everything seems exciting, different and fascinating. It’s an (33)______. If you are just on a short holiday, you will probably never leave this phase.
(34)_______, if you stay longer, your attitude can start to change. As you start to realize (35)_____ little you really understand the new culture, life can get frustrating. People misunderstand what you are trying to say, or they may laugh at you when you say something incorrectly. Even simple things, like posting a letter, can seem very difficult to you. Thus, you are likely to get angry or upset when things go wrong.
With time, though, you start to (36)______ to become more comfortable with the differences and better able to handle frustrating situations. Your (37)______ of humor reappears. Finally, you may feel enthusiastic about the culture once again, enjoy living in it, and even prefer certain aspects of the culture to your own.
(Adapted from Navigate – Coursebook, OUP 2015)
Điền ô 35
whether
how
if
what
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 33 to 37.
When you first arrive in a foreign culture, often your first reaction is completely positive. Everything seems exciting, different and fascinating. It’s an (33)______. If you are just on a short holiday, you will probably never leave this phase.
(34)_______, if you stay longer, your attitude can start to change. As you start to realize (35)_____ little you really understand the new culture, life can get frustrating. People misunderstand what you are trying to say, or they may laugh at you when you say something incorrectly. Even simple things, like posting a letter, can seem very difficult to you. Thus, you are likely to get angry or upset when things go wrong.
With time, though, you start to (36)______ to become more comfortable with the differences and better able to handle frustrating situations. Your (37)______ of humor reappears. Finally, you may feel enthusiastic about the culture once again, enjoy living in it, and even prefer certain aspects of the culture to your own.
(Adapted from Navigate – Coursebook, OUP 2015)
Điền ô 36
replace
maintain
adjust
keep
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 33 to 37.
When you first arrive in a foreign culture, often your first reaction is completely positive. Everything seems exciting, different and fascinating. It’s an (33)______. If you are just on a short holiday, you will probably never leave this phase.
(34)_______, if you stay longer, your attitude can start to change. As you start to realize (35)_____ little you really understand the new culture, life can get frustrating. People misunderstand what you are trying to say, or they may laugh at you when you say something incorrectly. Even simple things, like posting a letter, can seem very difficult to you. Thus, you are likely to get angry or upset when things go wrong.
With time, though, you start to (36)______ to become more comfortable with the differences and better able to handle frustrating situations. Your (37)______ of humor reappears. Finally, you may feel enthusiastic about the culture once again, enjoy living in it, and even prefer certain aspects of the culture to your own.
(Adapted from Navigate – Coursebook, OUP 2015)
Điền ô 37
taste
sense
touch
sound
Choose the item (A, B, C or D) that best completes the unfinished statement.
Sometimes people add to what they say even when they don't talk. Gestures are the "silent language" of every culture. We point a finger or move another part of the body to show what we want to say. It is important to know the body language of every country or we may be misunderstood. In the United States, people greet each other with a handshake in a formal introduction. The handshake must be firm. If the handshake is weak, it is a sign of weakness or unfriendliness. Friends may place a hand on the other's arm or shoulder. Some people, usually women, greet a friend with a hug.
Space is important to Americans. When two people talk to each other, they usually stand about two and a half feet away and at an angle, so they are not facing each other directly. Americans get uncomfortable when a person stands too close. They will move back to have their space. If Americans touch another person by accident, they say, "Pardon me." or "Excuse me." Americans like to look the other person in the eyes when they are talking. If you don't do so, it means you are bored, hiding something, or are not interested. But when you are stare at someone, it is not polite. For Americans, thumbs-up means yes, very good, or well done. Thumbs down means the opposite. To call a waiter, raise one hand to head level or above. To show you want the check, make a movement with your hands as if you are signing a piece of paper. It is all right to point at things but not at people with the hand and index finger. Americans shake their index finger at children when they scold them and pat them on the head when they admire them. Learning a culture's body language is sometimes confusing. If you don't know what to do, the safest thing to do is to smile
From the passage we can learn that_______.
gestures don't mean anything while talking
It's confusing to understand a culture's body language
gestures can help us to express ourselves
American people often use body language in communication
Choose the item (A, B, C or D) that best completes the unfinished statement.
Sometimes people add to what they say even when they don't talk. Gestures are the "silent language" of every culture. We point a finger or move another part of the body to show what we want to say. It is important to know the body language of every country or we may be misunderstood. In the United States, people greet each other with a handshake in a formal introduction. The handshake must be firm. If the handshake is weak, it is a sign of weakness or unfriendliness. Friends may place a hand on the other's arm or shoulder. Some people, usually women, greet a friend with a hug.
Space is important to Americans. When two people talk to each other, they usually stand about two and a half feet away and at an angle, so they are not facing each other directly. Americans get uncomfortable when a person stands too close. They will move back to have their space. If Americans touch another person by accident, they say, "Pardon me." or "Excuse me." Americans like to look the other person in the eyes when they are talking. If you don't do so, it means you are bored, hiding something, or are not interested. But when you are stare at someone, it is not polite. For Americans, thumbs-up means yes, very good, or well done. Thumbs down means the opposite. To call a waiter, raise one hand to head level or above. To show you want the check, make a movement with your hands as if you are signing a piece of paper. It is all right to point at things but not at people with the hand and index finger. Americans shake their index finger at children when they scold them and pat them on the head when they admire them. Learning a culture's body language is sometimes confusing. If you don't know what to do, the safest thing to do is to smile
If you are introduced to a stranger from the USA, you should _______.
greet him with a hug
place a hand on his shoulder
shake his hand weakly
shake his hand firmly
Choose the item (A, B, C or D) that best completes the unfinished statement.
Sometimes people add to what they say even when they don't talk. Gestures are the "silent language" of every culture. We point a finger or move another part of the body to show what we want to say. It is important to know the body language of every country or we may be misunderstood. In the United States, people greet each other with a handshake in a formal introduction. The handshake must be firm. If the handshake is weak, it is a sign of weakness or unfriendliness. Friends may place a hand on the other's arm or shoulder. Some people, usually women, greet a friend with a hug.
Space is important to Americans. When two people talk to each other, they usually stand about two and a half feet away and at an angle, so they are not facing each other directly. Americans get uncomfortable when a person stands too close. They will move back to have their space. If Americans touch another person by accident, they say, "Pardon me." or "Excuse me." Americans like to look the other person in the eyes when they are talking. If you don't do so, it means you are bored, hiding something, or are not interested. But when you are stare at someone, it is not polite. For Americans, thumbs-up means yes, very good, or well done. Thumbs down means the opposite. To call a waiter, raise one hand to head level or above. To show you want the check, make a movement with your hands as if you are signing a piece of paper. It is all right to point at things but not at people with the hand and index finger. Americans shake their index finger at children when they scold them and pat them on the head when they admire them. Learning a culture's body language is sometimes confusing. If you don't know what to do, the safest thing to do is to smile
The word “them” in paragraph 2 refers to
Americans
children
fingers
people
Choose the item (A, B, C or D) that best completes the unfinished statement.
Sometimes people add to what they say even when they don't talk. Gestures are the "silent language" of every culture. We point a finger or move another part of the body to show what we want to say. It is important to know the body language of every country or we may be misunderstood. In the United States, people greet each other with a handshake in a formal introduction. The handshake must be firm. If the handshake is weak, it is a sign of weakness or unfriendliness. Friends may place a hand on the other's arm or shoulder. Some people, usually women, greet a friend with a hug.
Space is important to Americans. When two people talk to each other, they usually stand about two and a half feet away and at an angle, so they are not facing each other directly. Americans get uncomfortable when a person stands too close. They will move back to have their space. If Americans touch another person by accident, they say, "Pardon me." or "Excuse me." Americans like to look the other person in the eyes when they are talking. If you don't do so, it means you are bored, hiding something, or are not interested. But when you are stare at someone, it is not polite. For Americans, thumbs-up means yes, very good, or well done. Thumbs down means the opposite. To call a waiter, raise one hand to head level or above. To show you want the check, make a movement with your hands as if you are signing a piece of paper. It is all right to point at things but not at people with the hand and index finger. Americans shake their index finger at children when they scold them and pat them on the head when they admire them. Learning a culture's body language is sometimes confusing. If you don't know what to do, the safest thing to do is to smile
When your friend give you a thumbs-up, he, in fact
shows his rudeness to you
shows his anger to you
expresses his satisfaction to you
expresses his worries about you
Choose the item (A, B, C or D) that best completes the unfinished statement.
Sometimes people add to what they say even when they don't talk. Gestures are the "silent language" of every culture. We point a finger or move another part of the body to show what we want to say. It is important to know the body language of every country or we may be misunderstood. In the United States, people greet each other with a handshake in a formal introduction. The handshake must be firm. If the handshake is weak, it is a sign of weakness or unfriendliness. Friends may place a hand on the other's arm or shoulder. Some people, usually women, greet a friend with a hug.
Space is important to Americans. When two people talk to each other, they usually stand about two and a half feet away and at an angle, so they are not facing each other directly. Americans get uncomfortable when a person stands too close. They will move back to have their space. If Americans touch another person by accident, they say, "Pardon me." or "Excuse me." Americans like to look the other person in the eyes when they are talking. If you don't do so, it means you are bored, hiding something, or are not interested. But when you are stare at someone, it is not polite. For Americans, thumbs-up means yes, very good, or well done. Thumbs down means the opposite. To call a waiter, raise one hand to head level or above. To show you want the check, make a movement with your hands as if you are signing a piece of paper. It is all right to point at things but not at people with the hand and index finger. Americans shake their index finger at children when they scold them and pat them on the head when they admire them. Learning a culture's body language is sometimes confusing. If you don't know what to do, the safest thing to do is to smile
The word “accident” in paragraph 2 is closest in meaning to
chance
mishap
misfortune
disaster
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.
Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun. In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than at the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas. This explanation, however, is of little use to most average people.
Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.
In paragraph 1, why does the author compare the structure of an atom to a solar system?
To provide an explanation of atomic structure that will be easily understood
To show the influence of atomic structure on the world at the observable level
To show that the complex mathematical formulas used to explain atomic structure are inaccurate
To contrast the size of atoms with the size of objects at the observable level
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.
Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun. In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than at the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas. This explanation, however, is of little use to most average people.
Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.
According to paragraph 2, an atom's atomic number is determined by __________.
the sum of its protons and electrons
the difference in the mass of its neutrons and protons
the strength of the bond between its protons and neutrons
the total number of protons it has
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.
Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun. In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than at the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas. This explanation, however, is of little use to most average people.
Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached
The word "stable" in bold in paragraph 2 is closest in meaning to _____.
neutral
unchanging
equal
heavy
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions
Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun. In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than at the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas. This explanation, however, is of little use to most average people.
Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.
Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps to keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbits. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electrons than the previous shell. Electrons naturally seek to occupy the lowest shell possible. So, if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light. This is why fires and other very hot objects seem to glow
According to the information in paragraph 2, what will happen if an atom has more neutrons than protons?
It will not have enough of a positive electrical charge to keep its electrons in orbit
Its extra neutrons will be converted into light energy
It will slowly give off neutrons until the atom becomes stable
Its nucleus will explode in a supernova
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.
Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun. In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than at the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas. This explanation, however, is of little use to most average people.
Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.
Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps to keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbits. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electrons than the previous shell. Electrons naturally seek to occupy the lowest shell possible. So, if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light. This is why fires and other very hot objects seem to glow.
The phrase "one another" in bold in paragraph 3 refers to _______.
electrons
electrical charges
particles
atoms
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.
Atomic were once thought to be fundamental pieces of matter, but they are in turn made of smaller subatomic particles There are three major subatomic particles neutrons, protons, and electronic. Protons and neutrons can be broken into even smaller units, but these smaller units not occur naturally in nature and are thought to only be produced in manmade particle accelerators and perhaps in extreme stellar events like supernovas. The structure of an atom can best be described as a small solar system, with the neutrons at the center and the electrons circling them in various orbits, just as the planets circle the sun. In reality, the structure of an atom is far more complex, because the laws of physics are fundamentally different at the atomic level than at the level of the observable word. The true nature of atomic structure can only be expressed accurately through complex mathematical formulas. This explanation, however, is of little use to most average people.
Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.
Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps to keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbits. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electrons than the previous shell. Electrons naturally seek to occupy the lowest shell possible. So, if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light. This is why fires and other very hot objects seem to glow.
According to paragraph 3, when does an atom produce light?
When it has more electrons than its electron shells can hold
When energy is added to the outermost electron shell
When an electron drops back to its original electron shell
When an electron is transferred from one atom to another
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.
Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.
Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps to keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbits. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electrons than the previous shell. Electrons naturally seek to occupy the lowest shell possible. So, if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light. This is why fires and other very hot objects seem to glow.
Electrons are also primarily responsible for many of the chemical properties of atoms. Since electrons seek to occupy the lowest electron shell possible, they will move from one atom to another if there is a space available in a lower electron shell. For example, if there is an atom with an open space in its third shell, and it comes into contact with an atom with electrons in its fourth shell, the first atom will take one of these electrons to complete its third shell. When this happens, the two atoms will be chemically bonded to form a molecule. Furthermore, atoms sometimes lose electrons in collisions with other atoms. When this happens, the radio of protons and electrons in the atom changes, and therefore, the overall electrical charge of the atom changes as well. These atoms are called isotopes, and they have significantly different chemical properties from their parent atoms
According to the passage, all of the following are true of electrons EXCEPT __________.
they are elementary particles and cannot be broken down
they are considerably smaller than neutrons or protons
their energy levels are fixed and unchanging
they are kept in orbit by electromagnetic attraction
Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions
Protons and neutrons have nearly equal mass and size, but protons carry a positive electrical charge, while neutrons carry no charge at all. Protons and neutrons are bound together by the strong nuclear force, one of the four basic forces in the universe. Protons and neutrons give atoms some of their most basic properties. Elements are defined by two numbers: their atomic number, which is equal to the number of protons they have, and their atomic weight, which is equal to total number of their neutrons and protons. In most lighter atoms, the number of neutrons and protons is equal, and the element is stable. In heavier atoms, however, there are more neutrons than protons, and the element is unstable, eventually losing neutrons through radioactive decay until a neutral state is reached.
Electrons are negatively charged particles. They are bound to their atoms through electromagnetic attraction. Opposite electrical charges attract one another, so the positive charge of the proton helps to keep the negatively charged electron in orbit around the nucleus of the atom. Electrons are different from neutrons in that they cannot be broken down into smaller particles. They are also far smaller and lighter than neutrons and protons. An electron is about one thousandth of the diameter of a proton and an even smaller fraction of its mass. Electrons circle the protons and neutrons at the center of the atom in orbits. These orbits are often called electron shells. The closer the orbit is to the center of the atom, the lower its energy is. There are seven electron shells, and each higher level can hold more electrons than the previous shell. Electrons naturally seek to occupy the lowest shell possible. So, if there is space in a lower shell, an electron will drop down to occupy that space. At temperatures higher than a few hundred degrees, electrons will gain energy and move to a higher shell, but only momentarily. When the electrons drop back down to their natural shell, they emit light. This is why fires and other very hot objects seem to glow.
Electrons are also primarily responsible for many of the chemical properties of atoms. Since electrons seek to occupy the lowest electron shell possible, they will move from one atom to another if there is a space available in a lower electron shell. For example, if there is an atom with an open space in its third shell, and it comes into contact with an atom with electrons in its fourth shell, the first atom will take one of these electrons to complete its third shell. When this happens, the two atoms will be chemically bonded to form a molecule. Furthermore, atoms sometimes lose electrons in collisions with other atoms. When this happens, the radio of protons and electrons in the atom changes, and therefore, the overall electrical charge of the atom changes as well. These atoms are called isotopes, and they have significantly different chemical properties from their parent atoms
According to paragraph 4, which property of electrons is responsible for chemical bonding?
Their electromagnetic attraction to protons
Their tendency to occupy the lowest possible electron shell
The fact that they cannot be broken into smaller particles
Their ability to break free of their atom during a collision

