Question

Ascorbic acid (vitamin C) has the molecular formula C H₂O (molar mass = 176.12 g/mol) The recommended daily allowance of

ascorbic acid in the diet of a human adult is 0.045 g. How many molecules of ascorbic acid is this?

Select one:

1.54 x 10^20molecules
2.56 x 10^-4molecules
2.71x 10^22 molecules
4.77 x 10^24 molecules

Answer 1

1.54 × 10²⁰ molecules

Step-by-step explanation:

Dividing the mass by the molar mass, we get the number of moles to be (0.045)/(176.12), which is about 0.0002555 mol.

Avogadro's law states that there are 6.022 × 10²³ molecules in one mole of a substance, so the answer is

(0.0002555)(6.022 × 10²³), which is 1.54 × 10²⁰ molecules.