Q3 Review: Molar Relationships and States of Matter

The number of molecules in 2.1 moles of CO₂ is:

• 1.26 x 10²⁴ molecules

• 2.52 x 10²⁴molecules

• 1.05 x 10²⁴ molecules

• 6.02 x 10²³ molecules

Determine the number of moles in 5.0 L of Ar gas (at STP).

• 0.223 moles

• 0.5 moles

• 5.0 moles

• 11.2 moles

Determine the mass in grams for 5.9 mol C₈H₁₈.

(you do not need to add grams to the end of your answer)

Empirical formula of C₃H₆

• C₃H₆

• C₃H₈

• C₂H₄

• CH₂

Empirical formula of C₁₂H₂₂O₁₁

• C₁₂H₂₂O₁₁

• CHO

• CH₂O

• CH₂

Calculate the empirical formula of a compound that has 75% carbon and 25% hydrogen by mass.

• CH₄

• C₂H₄

• C₃H₈

• CH₂

Calculate the empirical formula of the compound: An 88.0 g sample of a compound consisting of carbon and hydrogen contains 81.2 g of carbon and 6.8 g of hydrogen.

• CH

• C₂H₂

• CH₂

• C₂H₄

Using the following equation: Fe₂O₃ + 3H₂ --> 2Fe + 3H₂O, if 6 moles of H₂ reacted, then the number of moles of iron produced is:

• 2

• 4

• 6

• 8

Tags

NGSS.HS-PS1-7

Using the combustion reaction: C₃H₈ + 5O₂ -> 3CO₂ + 4H₂O, if 1.00 liter of oxygen gas is used, how many liters of carbon dioxide will be producted at standard temperature and pressure?

Remember, 1 mole = 22.4 L

• 0.6 liters

• 1.2 liters

• 1.8 liters

• 2.4 liters

Using the following equation: Li₃N + 3H₂O -> NH₃ + 3LiOH. Determine the mass of lithium hydroxide produced when 0.38 g of lithium nitride reacts with water.

• 0.45 g

• 0.60 g

• 0.78 g

• 0.90 g

Tags

NGSS.HS-PS1-7