This question is about the reduction of iron oxide with carbon.

(You may need a periodic table)

The equation for the reaction between iron oxide and carbon is below. 

Complete the balanced symbol equation for the reaction. 

Calculate the relative formula mass of iron oxide. 

Explain why carbon can be used to reduce iron but cannot be used to reduce magnesium.

Calculate the percentage atom economy to produce iron from the reduction of iron oxide.

Tungsten reacts with oxygen in the air to form tungsten oxide. 

Tungsten can be reduced by heating the tungsten oxide with hydrogen. 

Complete the balanced symbol equation for the reaction between tungsten oxide and hydrogen.2

Calculate the percentage atom economy for the reaction between tungsten oxide and hydrogen to produce tungsten. 

(You may need a periodic table)

A student is investigating the thermal decomposition of calcium carbonate. 

The equation for the reaction is 

CaCO_3(s) ➔ CaO_(s) + CO_2(g)

(You may need a periodic table)

The student heats 12.00 grams of calcium carbonate for 15 minutes.

After 15 minutes the mass of solid remaining is 4.14 grams. 

Calculate the mass of carbon dioxide given off. 

Calculate the relative formula mass of calcium carbonate, CaCO₃.

Calculate the percentage atom economy for the production of calcium oxide from calcium carbonate.

The student heated the calcium carbonate and measured the mass each minute for 10 minutes.

Plot a graph to show how the mass of solids varied over time.

Describe how the mass of solids remaining varies over time.

A student is completing a titration of sulfuric acid and sodium hydroxide. 

The equation for the reaction is below. 

Complete the balanced symbol equation for the reaction between sulfuric acid and sodium hydroxide. 

Calculate the relative formula mass of sodium sulfate, Na₂SO₄.

(You may need a periodic table)

Calculate the percentage atom economy for the production of sodium sulfate from sulfuric acid and sodium hydroxide.

Relative formula mass of sulfuric acid (H₂SO₄) = 98

Relative formula mass of sodium hydroxide (NaOH) = 40

A student heats zinc carbonate over a Bunsen burner. 

The zinc carbonate thermally decomposes to form zinc oxide and carbon dioxide.

The student predicts the yield should be 0.73 g.

The student actually obtains 0.63 g of zinc oxide. 

State the equation for percentage yield.

Calculate the percentage yield for the students experiment. 

The student started with 1.2 g of zinc carbonate and obtained 0.63 g of zinc oxide. 

Calculate the mass of carbon dioxide released.

This question is about the production of nitric acid. 

Company A produces nitric acid by reacting ammonia with oxygen.

Company B produces nitric acid by reacting water with nitrogen dioxide.

The equations for the two reactions are below.

Company A:    NH₃ + 2O₂ ➔ HNO₃ + H₂O

Company B:    3NO₂ + H₂O ➔ 2HNO₃ + NO

Calculate the percentage atom economy for the production of nitric acid for company B. 

Use the information in the table below.

Company A predicts they should produce 12.4 tonnes of nitric acid. 

The actual yield company A records is 10.9 tonnes. 

Calculate the percentage yield of nitric acid.

Give one advantage of a high atom economy.

Do not mention costs in your answer.

Give one advantage of a very high percentage yield.

Do not mention costs in your answer.

A student is reducing zinc oxide with carbon. 

The equation for the reaction is

ZnO + C ➔ Zn + CO

(You may need a periodic table)

Which of the following represents the percentage atom economy for the production of zinc?

The student starts with 4.0 g of zinc oxide.

Calculate the mass of carbon required to reduce the 4.0 g sample of zinc oxide.

The student predicts that the reaction should yield 3.2 g of zinc. 

The student records the mass of zinc produced to be 2.7 g.

Calculate the percentage yield of zinc. Give your answer to 1 decimal place.

In industry, companies strive to increase their percentage yield. 

Explain one reason - other than cost - why increasing percentage yield is advantageous.