IGCSE Chemistry Metals topical questions

Pieces of magnesium, iron and copper are each added to separate tubes of dilute hydrochloric acid. Magnesium fizzes rapidly, iron fizzes slowly, and copper shows no change.

1. (a)State which metal is the most reactive.[1]
2. (b)Name the gas released by the reacting metals.[1]
3. (c)State which metal does not react with the acid.[1]

A steel garden gate is to be protected from rusting.

1. (a)Name one suitable barrier method.[1]
2. (b)Explain how this method prevents rusting.[1]

Give a metal and the property that suits it for each use.

1. (a)Name a metal used for the body panels of aircraft and state the property that makes it suitable.[2]
2. (b)Name a metal used for electrical wiring and state the properties that make it suitable.[2]

An iron nail is left in a tube of blue copper(II) sulfate solution overnight.

1. (a)State two observations.[2]
2. (b)Write the ionic equation for the reaction.[1]
3. (c)Use the reactivity series to explain why the reaction happens.[1]

Aluminium is high in the reactivity series but aluminium window frames last outdoors for decades.

1. (a)Predict how a clean piece of aluminium would behave if added to dilute hydrochloric acid.[1]
2. (b)Explain why aluminium appears unreactive in everyday use.[2]
3. (c)Explain why aluminium food containers do not corrode away in use.[1]

A student adds a piece of zinc to aqueous copper(II) sulfate. In a second tube, a piece of copper is added to aqueous zinc sulfate.

1. (a)State two observations in the first tube.[2]
2. (b)State the observation in the second tube.[1]
3. (c)State the conclusion about the reactivity of zinc and copper.[1]

A strip of magnesium ribbon is cleaned with sandpaper and added to excess dilute hydrochloric acid. The hydrogen produced is collected in a gas syringe.

1. (a)Suggest why the ribbon is cleaned with sandpaper first.[1]
2. (b)Name the salt formed in the reaction.[1]
3. (c)Write the symbol equation for the reaction.[2]

In the blast furnace, iron is extracted from hematite, which is mainly iron(III) oxide.

1. (a)Name the reducing agent that converts the iron(III) oxide to iron.[1]
2. (b)Write the symbol equations for the two reactions that make this reducing agent inside the furnace.[2]
3. (c)Write the symbol equation for the reduction of iron(III) oxide.[1]
4. (d)Explain the purpose of adding limestone to the furnace.[1]

Aluminium is extracted by electrolysis of molten aluminium oxide dissolved in cryolite.

1. (a)Write the ionic half-equation for the reaction at the cathode.[1]
2. (b)Write the ionic half-equation for the reaction at the anode.[1]
3. (c)Explain why the carbon anodes must be replaced regularly.[2]
4. (d)Explain why aluminium cannot be extracted by heating its oxide with carbon.[1]

An underground steel pipeline is protected by attaching blocks of magnesium to it at intervals.

1. (a)State why the protecting metal must be more reactive than iron.[1]
2. (b)Explain, in terms of electrons, how the magnesium protects the pipeline. (Supplement)[2]
3. (c)State what eventually happens to the magnesium blocks.[1]
4. (d)Explain why blocks of copper would not protect the pipeline.[1]