Ester no, đơn chức, mạch hở có công thức chung là

$\text{C}{}_{\text{n}}\text{H}{}_{2\text{n}}\text{O}{}_2(\text{n}\ge 2)$.

$\text{C}{}_{\text{n}}\text{H}{}_{2\text{n}}\text{O}{}_2(\text{n}\ge 1)$.

$\text{C}{}_{\text{n}}\text{H}{}_{2\text{n}+2}\text{O}{}_2(\text{n}\ge 2)$.

$\text{C}{}_{\text{n}}\text{H}{}_{2\text{n}-2}\text{O}{}_2(\text{n}\ge 2)$.