Chemical Quantities Review for Test

What is the formula mass of CO₂?

• 44 grams
• 44 amu
• 0.44 grams
• 2.6 x 10²⁵ atoms

What is the percent composition of nitrogen in NH₃?

• 25%
• 14%
• 28%
• 82%

Which of the following is an empirical formula?

• C₃H₃
• Li₂CO₃
• Na₂O₂
• C₆H₁₂O₆

How many moles are contained in 45 grams of aluminum?

• 27 mol
• 1215 mol
• 1.7 mol
• 57 mol

How many moles of chlorine gas are contained in 45 grams of pure sample?

• 35 mol
• 0.64 mol
• 1.3 mol
• 2.6 mol

How many atoms of sodium are contained in a mole of sodium?

• 6.02 x 10²³ atoms

• 11 atoms

• 23 atoms

• 2 atoms

If the empirical formula is CH and the molar mass of the compound is 78g/mol, what is the molecular formula?

• C₆H₆

• C₅H₁₈

• CH

• 6CH

How many moles are in 16.94g of water?

• 16.94 mol H₂O
• 0.9401 mol H₂O
• 305.3 mol H₂O
• 1.063 mol H₂O

How many grams are in 1.2 x 10²⁴ molecules of CO?

• 28 grams
• 56 grams
• 6.02 grams
• 1.2 grams

A container with a volume of 893 L contains how many moles of air at STP?

• 20003.2 L
• 39.9 L
• 22.4 L
• none of the choices