Empirical Formula

A compound consists of 72.2% magnesium(Mg) and 27.8% nitrogen(N) by mass. What is the empirical formula?

• Mg₄N₃
• MgN₂
• Mg₃N₂ 
• MgN

How many molecules are in 2.5 mol of NaCl?

• 1.5 x 10²⁴ molecules

• 1.5 molecules

• 4.15 molecules

• 1.5 x 10²³ molecules

Which pair has the same empirical formula?

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

A formula with the lowest whole # ratio of elements in a compound is called

• Molecular Formula
• Chemical Formula
• Empirical Formula 
• Distance Formula

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

Which one is an empirical formula?

• H₂O₂
• C₂H₆O₁₂
• CaCl₂
• N₂O₈

What is the empirical formula for C₃H₈

• CH
• C₃H₈
• C₆H₁₆
• CH_2.7

P₂O₆

• P₂O₆

• PO

• PO₃

• P₃O

An empirical formula:

• is the simplest whole-number ratio of moles of elements in the compound,

• is a formula that calculates the coefficients of a compound in a balanced equation.

A 5.00 g sample of a compound consisting of calcium and chlorine contains 1.82 g of calcium and 3.23 g of chlorine. What is the empirical formula

• CaCl₂

• Ca₂Cl₂

• Ca₂Cl₄

• Ca₄Cl₂