Question

Ascorbic acid has a molar mass of 176.14 g/mol. What is the molecular formula of ascorbic acid? The empirical formula is C3H4O3.Express your answer as a chemical formula.

Answer 1

The molecular formula of ascorbic acid is determined by doubling the empirical formula C3H4O3, resulting in C6H8O6, due to the molar mass being 176 g/mol, which is twice the mass of its empirical formula, 88.062 g/mol.

Step-by-step explanation:

The molecular formula of a compound represents the actual number of atoms of each element in a molecule. To find the molecular formula for ascorbic acid, we first need to calculate the molar mass of its empirical formula, which is C3H4O3. The molar mass for the empirical formula is (3 × 12.011) + (4 × 1.008) + (3 × 15.999) = 88.062 g/mol.

Given that the experimentally determined molecular mass of ascorbic acid is 176 amu, we divide this value by the molar mass of the empirical formula to find the multiple:

176 g/mol ÷ 88.062 g/mol = 2

Since the multiple is 2, we multiply the subscripts in the empirical formula by 2 to obtain the molecular formula:

C3H4O3 × 2 = C6H8O6

Therefore, the molecular formula of ascorbic acid is C6H8O6.

Answer 2

Step 1 - Determine the mass of the empirical formula C3H4O3. Molar mass values: C = 12 g/mol; O = 16 g/mol; H = 1g/mol

(3x12) + (4x1) + (3x16) = 88 g/mol

Step 2 - Calculate the molecular formula:

88 g ---- 1 mol

176.14 g ---- x mol

x = 2 mol

This means that we need 2 minimum formulas to arrive at the molar mass of the compound. So, just multiply the element indices of the empirical formula by 2 to find the molecular formula, which is: C6H8O6

Answer: The molecular formula is C6H8O6