%comp and Empirical and Molecular Formulas

Which pair has the same empirical formula?

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

What is the percent by mass of oxygen in MgO?

• 20%
• 40%
• 50%
• 60%

What is the percent by mass of sodium in NaCl?

• 39%
• 61%
• 35%
• 65%

Tags

NGSS.HS-PS1-7

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

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

What is the empirical formula for: C₄H₆

• CH

• CH₃

• C₂H₃

• C₄H₆

What is the empirical formula for: Br₂O₆

• BrO₃

• Br₆O₂

• BrO

• Br₂O₆

What is the empirical formula for: N₂S₃

• NS

• N₃S₂

• N₂S₃

What is the empirical formula for: C₂₅H₄₅

• C₂₅H₄₅

• CH

• C₅H₉

• C₉H₅

What is the percent composition by mass of sulfur in the compound MgSO₄ (molar mass of MgSO₄ = 120 g/mol)?

• 20%

• 27%

• 46%

• 53%

Si₂F₆

Choose the correct empirical formula...

• SiF

• Si₂F₆

• SiF₃

• Si₆F₂