Question

structural formula homework
write the formula of each molecule:

Explanation:

Step1: Identify first molecule

It is benzoic - acid. Count atoms.
$C_7H_6O_2$

Step2: Identify second molecule

It is a 9 - carbon ketone. Count atoms.
$C_9H_{18}O$

Step3: Identify third molecule

It is a type of amino - acid. Count atoms.
$C_4H_9NO_4$

Answer:

$C_7H_6O_2$, $C_9H_{18}O$, $C_4H_9NO_4$