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The empirical formula of a compound is CH₂. It's molecular mass is 70.15 g/mol. What is the molecular formula?

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Answer:

C₅H₁₀.

Step-by-step explanation:

To determine the molecular formula of the compound, we need to know the molar mass of the compound. Since the empirical formula is CH₂, the empirical molar mass can be calculated as:

Empirical molar mass = 12.01 g/mol (atomic mass of C) + 2(1.01 g/mol) (atomic mass of H)

Empirical molar mass = 14.03 g/mol

The molecular mass of the compound is given as 70.15 g/mol. To find the molecular formula, we need to know how many empirical units are present in the molecule. This can be calculated by dividing the molecular mass by the empirical molar mass:

Number of empirical units = Molecular mass / Empirical molar mass

Number of empirical units = 70.15 g/mol / 14.03 g/mol

Number of empirical units = 5

This means that there are 5 empirical units (CH₂) present in the molecular formula of the compound. Therefore, the molecular formula is:

Molecular formula = 5(CH₂) = C₅H₁₀

Thus, the molecular formula of the compound is C₅H₁₀.

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