% composition, empirical and molecular

What percent of Zn₃(PO₄)₂ is zinc?

• 33.15%
• 16.04%
• 50.81%
• 19.68%

What is the empirical formula if you have 36.84% nitrogen and 63.16% oxygen?

• NO
• N₂O₃
• N₂O₄
• N₂O₅

An empirical formula:

• is a formula that calculates the coefficients of a compound in a balanced equation.
• is the simplest whole-number ratio of moles of elements in the compound.

Which pair has the same empirical formula?

• NaCrO₄ and Na₂Cr₂O₇
• C₂H₄O₂ and C₆H₁₂O₆
• C₃H₆O₃ and C₂H₆O₂
• CH₄ and C₂H₆

What is the molecular formula if the empirical formula is CH₂O and the molecular molar mass is 180.18?

• CH₂O
• C₂H₄O₂
• C₄H₈O₄
• C₆H₁₂O₆

A chemical formula that shows the actual # and kinds of atoms present in one molecule of a compound is called_________

• ionic formula
• covalent formula
• empirical formula
• molecular formula

A compound with the following composition has a molar mass of 60.10g/mol: 39.97% carbon; 13.41% hydrogen; 46.62% nitrogen. Find the empirical and molecular formula.

• CHN, CH₂N₄

• CH⁴N, C₂H₄N

• CH₄N, C₂H₈N₂

• none of the above are correct