Chemistry final

Types of chemical reactions: Which type of chemical reaction is this? H₂SO₄ + Fe ⟶ H₂ + FeSO₄.

• combustion

• single replacement

• double replacement

• synthesis

Types of chemical reactions: Which type of chemical reaction is this? 2 NO₂ ⟶ 2 O₂ + N₂.

• double replacement

• single replacement

• decomposition

• synthesis

Molar mass: What is the molar mass of NaClO₃?

• 39.998 g NaClO₃ = 1 mol NaClO₃

• 58.44 g NaClO₃ = 1 mol NaClO₃

• 74.44 g NaClO₃ = 1 mol NaClO₃

• 106.44 g NaClO₃ = 1 mol NaClO₃

Molar mass: What is the molar mass of MgCO₃?

• 148.3 g MgCO₃ = 1 mol MgCO₃

• 120.336 g MgCO₃ = 1 mol MgCO₃

• 95.211 g MgCO₃ = 1 mol MgCO₃

• 84.3139 g MgCO₃ = 1 mol MgCO₃

Moles: How many grams are equal to 3.46 moles of Na₂S (molar mass 78.0452)?

• 81.5 g

• 74.6 g

• 270 g

• 22.6 g

Moles: How many atoms are equal to 1.5 moles of helium?

• 0.067 atoms

• 33.6 atoms

• 4.01 x 10²³ atoms

• 9.03 x 10²³ atoms

Moles: How many liters would 2.25 mol of gas occupy at STP?

• 24.65 L

• 20.15 L

• 50.4 L

• 9.95 L

Stoichiometry: How many moles of Cu are needed to produce 0.25 moles of Cu₂S according to the following reaction: 2 Cu + S → Cu₂S

• 0.125 mol Cu

• 0.25 mol Cu

• 0.5 mol Cu

• 1.5 mol Cu

Stoichiometry: How many g of Ag₂O (molar mass 231.735) are needed to react with 7.9 g of HCl (molar mass 36.458)? Ag₂O + 2 HCl → 2 AgCl + H₂O

• 0.621 g Ag₂O

• 2.48 g Ag₂O

• 25.1 g Ag₂O

• 100.4 g Ag₂O

Mixtures & solutions: Calculate the molarity if there are 10 mol of NaCl in 5 L of solution.

• 1 M

• 2 M

• 5 M

• 15 M