Properties of Metals (Cambridge (CIE) O Level Chemistry): Exam Questions

Strontium and zinc are both metals with a valency of 2. Strontium is more reactive than zinc. Its chemistry is similar to that of calcium.

i) Complete the following table that shows the number of protons, electrons and neutrons in each particle.

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ii) Explain why and  are isotopes.

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The major ore of strontium is its carbonate, SrCO₃. Strontium is extracted by the electrolysis of its molten chloride.

i) Name the reagent that will react with the carbonate to form the chloride.

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ii) The electrolysis of molten strontium chloride produces strontium metal and chlorine. Write ionic equations for the reactions at the electrodes.

negative electrode (cathode) .............. positive electrode (anode) ................

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iii) One of the products of the electrolysis of concentrated aqueous strontium chloride is chlorine. Name the other two.

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Both metals react with water.

i) Write a word equation for the reaction of zinc and water and state the reaction conditions.

word equation .........

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conditions ............

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ii) Write an equation for the reaction of strontium with water and give the reaction condition.

equation .........

[2]

condition .........

[1]

This question is about metals and non-metals.

Compare the properties of metals and non-metals.

The Group I metals exhibit some properties that the majority of metals do not share.

Give one example of a property of Group I metals that is different from most other metals.

For each of the metals below, complete the table to identify a use of the metals and state the most important property of the metal that makes it suitable for that use.

An aluminium alloy containing 0.7% magnesium and 0.4% silicon by mass is used for making masts for sailing boats.

Calculate the number of moles of magnesium and silicon present in a mast with a mass of 17 kg.

[A_r (Mg) = 24;      A_r (Si) = 28]

Some metals react with cold water.

Give the balanced symbol equation for the reaction of calcium reacting with water. Include state symbols.

Using oxidation numbers, show that calcium is oxidised during the reaction with water.

A student added 20 cm³ of dilute hydrochloric acid to two boiling tubes. To one of the boiling tubes they added a small piece of calcium and to the other they added a small piece of magnesium.

State two observations that the student would make and how the observations would differ between the two boiling tubes.

The student had added the exact amount of magnesium required to react with the hydrochloric acid used. After carrying out the experiment, the student accidentally added some more magnesium. The student was surprised that the extra magnesium still reacted although the reaction was a lot slower. 

Explain these observations. Include an equation in your answer.