Unit 7 Review (Chemistry)

_____________________ uses balanced chemical equations to determine the number of moles or mass of reactants and/or products.

• Mole conversions

• Stoichiometry

• Molemetry

• Hydrometry

Tags

NGSS.HS-PS1-7

For the equation, N₂ + 3 H₂ → 2 NH₃, which of the following correctly identifies the given and wanted/unknown compounds if you are asked: how many grams of NH₃ are created from 5.6 moles of N₂?

• Given = NH₃; wanted = N₂

• Given = N₂; wanted = H₂

• Given = N₂; wanted = NH₃

• Given = H₂; wanted = NH₃

Tags

NGSS.HS-PS1-7

In the equation, 2 Al₂O₃ → 4 Al + 3 O₂, what is the mole ratio of aluminum to oxygen?

• 10:6

• 3:4

• 2:3

• 4:3

Tags

NGSS.HS-PS1-7

For the reaction represented by the equation, AgNO₃ + NaCl → NaNO₃ + AgCl, how many moles of silver chloride, AgCl, are produced from 7.0 mole of silver nitrate, AgNO₃?

• 1.0 mol

• 2.3 mol

• 7.0 mol

• 21 mol

Tags

NGSS.HS-PS1-7

Sulfur dioxide (SO₂) is an unwelcome result of burning soft coal in power plants, such as Plant Bowen. Some of the SO₂ ends up as sulfuric acid in acid rain. The net reaction is as follows: 2 SO₂ (g) + O₂ (g) + 2 H₂O (l) → 2 H₂SO₄ (l). What mass in grams of SO₂ is needed to react with 37.50 mol O₂?

• 4,805.25g SO₂

• 2,402.63 g SO₂

• 32.04 g SO₂

• 128.04 g SO₂

To find how many grams of hydrogen are produced if 120 grams of sodium is reacted with water in the equation, 2 Na + 2 H₂O → 2 NaOH + H₂, which of the following do you need?

• Molar mass of hydrogen

• Molar mass of hydrogen and molar mass of sodium

• Balanced equation

• Molar mass of hydrogen, molar mass of sodium, and balanced equation

Tags

NGSS.HS-PS1-7

Using the balanced equation, 3 FeCl₂ + 2 Na₃PO₄ → 6 NaCl + Fe₃(PO₄)₂, which of the following mole ratios would you need to multiply 0.314 moles of Na₃PO₄ by to find the moles of NaCl produced?

• 3/6

• 1/6

• 2/6

• 6/2

Tags

NGSS.HS-PS1-7

Kristen is asked how many grams of iron (III) oxide, Fe₂O₃ (molar mass = 159.7 g/mol), can be produced from 25.0 g of iron (molar mass = 55.85 g/mol), according to the equation: 4 Fe + 3 O₂ → 2 Fe₂O₃. She sets the following calculation. What does she need to put in the blank?

• 25.0 g/1 mol Fe

• 1 mol Fe/159.7 g Fe₂O₃

• 159.7 g Fe₂O₃/1 mol Fe₂O₃

• 1 mol Fe/55.85 g Fe

Tags

NGSS.HS-PS1-7

Adam is asked how many grams of potassium bromide, KBr (molar mass = 119 g/mol), is produced from 1 mole of potassium chloride (KCl), in the following equation: Cl₂ + 2 KBr → 2 KCl + Br₂. He has set up the following calculation. What is he missing from the blank?

• 1 mol KBr/2 mol KCl

• 119 g KBr/1 mol KBr

• 1 mol Br₂/119 g KBr

• 2 mol KBr/119 g KBr

Trevor is asked to find the mass of H₂ produced when 0.600 grams of aluminum foil is reacted with excess hydrochloric acid in the reaction, 2 Al + 6 HCl → 2 AlCl₃ + 3 H₂. He sets up the equation as shown. The teacher tells him the answer is incorrect. What did he do wrong?

• He did not balance the equation.

• He used the incorrect molar ratio for aluminum and aluminum chloride.

• He used the incorrect molar mass for aluminum.

• He used the incorrect molar mass for hydrogen.

Tags

NGSS.HS-PS1-7