Calculating Formulas

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

• NO
• N₂O₃
• N₂O₄
• N₂O₅

You are given the following percentages: 40.05% S and 59.95% O. Find the empirical formula for these elements. (keep two decimal places throughout calculations)

• SO
• SO₂
• SO₃
• SO₄

What is the empirical formula of the following molecular formula:  C₃H₆

• C₃H₆
• CH₂
• C₂H₄
• CH₃

What is the empirical formula for the following:
32.40% sodium, 22.5% sulfur; 45.1 % oxygen, 37.75% water?

• Na₂SO₄H₆O₃
• Na₂SO_{4 .} 2H₂O
• Na₂SO_{4 .} 3H₂O
• Na₂SO_{4 .} (H₂O)₃

Tags

NGSS.HS-PS1-7

Find the percent composition of N₂S₂.

• N: 69.6%  S: 30.4%
• N:36% S: 75.6%
• N: 96.6% S: 3.4%
• N: 30.4% S: 69.6%

What is the molecular formula if the empirical formula is C₂H₅ and the molecular molar mass is 58.14 g/mol?

• C₂H₅
• C₄H₁₀
• C₁H_2.5
• C₄H₈

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

• CH₂O
• C₂H₄O₂
• C₄H₈O₄
• C₆H₁₂O₆

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

• C₂O₄H₈
• C₈O₂H₄
• C₄O₂H₈
• C₄O₈H₂

How many moles are in 88 g of propane, C₃H₈. 

• 2.0
• 16.0
• 0.051
• 3,872

Epinephrine (adrenaline) is a hormone secreted into the bloodstream in times of stress. It contains 59.0% C, 7.15% H, 26.20%O, 7.65%N and has a molar mass of 183 g/mol. What is its molecular formula?

• C₉H₁₃NO₃

• C₅H₁₁N₃O₂

• C₈H₁₂NO₂

• C₇H₉N₂O

Tags

NGSS.HS-LS1-6