Test 2

Carbon monoxide, a deadly gas, has a chemical formula of CO (one carbon atom with one oxygen atom). If you look at the total atomic mass of CO, does carbon or oxygen make up more of the mass?

• carbon

• oxygen

• they are exactly the same

• it is impossible to tell

What percentage of the total atomic mass of carbon monoxide (CO) is composed of carbon?

• 29%

• 43%

• 57%

• 73%

What percentage of the total atomic mass of carbon monoxide (CO) is composed of oxygen?

• 29%

• 43%

• 57%

• 73%

What percentage of the total atomic mass of calcium nitrate (Ca(NO₃)₂) is composed of nitrogen? Hint - another way to think of calcium nitrate is Ca(NO₃)(NO₃).

• 17%

• 24%

• 29%

• 59%

What is the empirical formula of a substance with the molecular formula C₂H₄?

• C₂H₂

• C₂H₂

• C₁H₁

• CH₂

Which pair has the same empirical formula?

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

Glucose has the formula C₆H₁₂O₆. Maltose has the chemical formula C₁₂H₂₂O₁₁. Do the have the same empirical formula?

• Yes

• No

Which of these is NOT an empirical formula?

• CH2

• C2H5

• C6H4

• C3H7

• C5H17

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

• SO

• SO₂

• SO₃

• SO₄

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

• NaPO₂

• Na₂PO₃

• Na₃PO₄

• NaPO₄