Moles, Empirical & Molecular Formulas, Hydrates

You are given the following percentages: 40.05% S and 59.95% O. Find the empirical formula for these elements.

• SO

• SO₂

• SO₃

• SO₄

What is the empirical formula for N₂S₃?

• NS

• N₃S₂

• N₂S₃

• N₁S_1.5

Tags

NGSS.MS-PS1-1

Given the following: 42.07% Na, 18.89% P, and 39.04% O, determine the empirical formula.

• NaPO₂

• Na₂PO₃

• Na₃PO₄

• NaPO₄

Tags

NGSS.HS-PS1-2

What is the empirical formula if you have 81.82% carbon and 18.18% hydrogen?

• C3H8
• CH4
• C2H2
• C4H10

What is the percent composition by mass of oxygen in the compound MgSO₄ (gram formula mass = 120 g/mol)?

• 20%
• 27%
• 46%
• 53%

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

• CH₂O
• C₂H₄O₂
• C₄H₈O₄
• C₆H₁₂O₆

Glycerol has a molar mass of 92.09g/mol. Its percent composition is: 39.12% C, 8.75% H, and 51.12% O. What is the molecular formula for glycerol?

• C₂H₃O₂
• CH₂O
• C₂H₄O₂
• C₃H₈O₃

What is the mass of 0.75 moles of (NH₄)₃PO₄?

• 101.75 g
• 121.75 g
• 111.75 g
• 131.75 g

Determine the amount of moles in CuBr that are in 276.9 g of the compound.

• 3.2 mol

• 1.7 mol

• 2.1 mol

• 1.9 mol

Tags

NGSS.HS-PS1-7

Determine the number of moles of Mg₃P₂ that are in 583 g of the compound.

• 2.9 mol

• 6.1 mol

• 4.3 mol

• 1.7 mol

Tags

NGSS.HS-PS1-7