Chemical quantities - Six weeks review

How many hydrogen atoms are in the compound: (NH₄)₂CO₃

• 3
• 4
• 6
• 8

Tags

NGSS.HS-LS1-6

What is the formula mass of CO₂?

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

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 are contained in a mole of sodium?

• 6.02 x 10²³ atoms
• 11 atoms
• 23 atoms
• 2 atoms

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

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

What is the percent composition of Benzene, C₆H₆?

• C = 50%
  H = 50%
• C = 85.7 %
  H = 14.3%
• C = 92.2%
  H = 7.8%
• C = 71.9%
  H = 28.1%

Tags

NGSS.HS-PS1-1

If 45.0 g of Mg react with 19.5 g of oxygen, what is the % of magnesium in the resulting compound?

• 69.8%

• 30.2%

• 43.3%

• 12.9%