A compound has an empirical formula of CH\(_2\) and a molar mass of 30.069 g/mol. What is its molecular formula?

• A. C\(_2\)H\(_6\)
• B. C\(_2\)H\(_4\)
• C. CH\(_2\)
• D. C\(_3\)H\(_6\)

Answer: (A)

Verified step by step guidance

1. Determine the molar mass of the empirical formula CH\(_2\). Calculate it by adding the atomic masses of carbon and hydrogen: \$12.01\, \text{g/mol}\( for C and \)1.008\, \text{g/mol}\( for H. So, the empirical formula mass is \)12.01 + 2 \times 1.008$.
2. Calculate the ratio of the compound's molar mass to the empirical formula mass using the formula: \(n = \frac{\text{Molar mass of compound}}{\text{Empirical formula mass}}\).
3. Use the value of \(n\) to find the molecular formula by multiplying each subscript in the empirical formula by \(n\). For example, if \(n=2\), then the molecular formula is \(\text{C}_{2}\text{H}_{4}\).
4. Write the molecular formula with the new subscripts obtained from the multiplication in step 3.
5. Verify that the molecular formula's molar mass matches the given molar mass of the compound to confirm the correct molecular formula.