Question

Determine the molecular formula for glucose, with a molar mass of 180 grams, if the empirical formula for glucose is CH2O.

CH2O

C2H4O2

C3H6O3

C6H12O6

Answer 1

the empirical formula for glucose is the simplest ratio of whole numbers components in the compound. While molecular formula is the actual composition of components in the compound.
Empirical formula has been given. We need to find the mass of one empirical unit
Mass of one empirical unit = CH₂O
= (12 g/mol x1 + 1 g/mol x 2 + 16 g/mol x 1) = 30 g
we need to find how many empirical units are there in the molecular formula
mass of molecule - 180 g/mol
how many empirical units in 1 molecule - 180 /30 = 6
therefore 6 empirical units = CH₂O x 6
molecular formula = C₆H₁₂O₆