Empirical and Molecular Formulas Quiz

A sample with a molar mass of 34.00 g/mol is found to consist of 0.44g H and 6.92g O. Find its molecular formula.

What is the molecular formula of the compound?

• HO

• H₂O

• HO₂

• H₂O2

If 4.04g of N combine with 11.46g O to produce a compound with a molar mass of 108.0 g/mol, what is the molecular formula of this compound?

What is the empirical formula of the compound?

• NO

• NO₂

• NO₅

• N₂O₅

2.40 g of an explosive, J, contains 0.473 g of nitrogen. J also contains 33.8% carbon and 1.41% hydrogen by mass. The remainder of J is oxygen.

What is the empirical formula of J?

• C₄HNO₂

• CH₂N₂O

• C₂HNO₂

• CHNO

Certain hormone secreted into the bloodstream contains 59.0% C, 7.15% H, 26.20% O, and 7.65% N with a molar mass of 183 g/mol. Find its molecular formula.

• C₇H₉N₂O

• C₉H₁₃NO₃

• C₅H₁₁N₃O₂

• C₈H₁₂NO₂

If 2.8 g of nitrogen combines with 6.4 g of oxygen, what is the empirical formula of the nitrogen oxide formed?

• NO

• N₂O

• NO₂

• N₂O₃

What mass of cobalt must have reacted if 3.20 g of oxygen forms 7.92 g of cobalt oxide?

• 3.20 g

• 4.72 g

• 7.92 g

What is the molecular formula of a compound with an empirical formula of C₂OH₄ and a molecular mass of 88 grams per mole?

• C₂O₄H₈

• C₈O₂H₄

• C₄O₂H₈

• C₄O₈H₂

What is the empirical formula for a compound which contains 67.1% zinc and the rest is oxygen?

• ZnO

• ZnO₂

• Zn₂O₄

• Zn₂O

Find the empirical formula for a compound which contains 32.8% chromium and 67.2% chlorine.

• CrCl

• CrCl₃

• Cr₃Cl

• Cr₂Cl₆

Si₂F₆

Choose the correct empirical formula...

• SiF

• Si₂F₆

• SiF₃

• Si₆F₂