Monosaccharides are generally defined by which of the following carbon to hydrogen to oxygen ratios?

(CHO2) n

(C2HO) n

(CH2O) n

(CHO) n

The answer is (CH2O) n.

Monosaccharides consists of carbon, hydrogen, and oxygen in ratio 1:2:1.

The basic formula of m onosaccharides is (CH2O) n. Let's take for example a glucose, which is monosaccharide. It is known that the formula of the glucose is C6H12O6, which means that it consists of 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms. So, in formula (CH2O) n, it must be n=6, so a glucose can be also represented as (CH2O) 6.