Questions

Q1.
 Sodium chloride solution can be prepared by reacting sodium hydroxide solution with an acid.
Give the name of the acid that must be used.
(1)
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Q2.

      Acids also react with metal carbonates.
      The word equation for the reaction of copper carbonate with dilute nitric acid is
copper 	(s) + 	nitric 	(aq)  → 	copper 	(aq)  + 	carbon 	(g)   +   water (l) 	
carbonate 	%%% 	acid 	%%% 	nitrate 	%%% 	dioxide 	%%% 	
 (i) State two things you would see when solid copper carbonate reacts with dilute nitric acid.
(2)
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(ii) Write the balanced equation for the reaction of copper carbonate with dilute nitric acid.
(3)
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Q3.
The decomposition of calcium carbonate produces calcium oxide.
Calcium oxide reacts with water.
The equation for the reaction is
CaO + H2O → Ca(OH)2 
(i)   5.6 g of calcium oxide reacts with water to form 7.4 g of calcium hydroxide.
Calculate the mass of the water that has reacted.
(1)
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answer = ..................................................................................g
(ii)  Describe how the solid calcium hydroxide could be used to test for carbon dioxide.
(2)
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Q4.
Chemical reactions
(a) Complete the sentence by putting a cross () in the box next to your answer.
When dilute hydrochloric acid reacts with copper oxide one of the products is
(1)
    A  copper
    B  copper hydroxide
    C  copper chlorate
    D  copper chloride
(b) Chlorine is manufactured by electrolysis.
Explain what is meant by electrolysis.
(2)
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(c) Chlorine gas reacts with sodium hydroxide solution to form sodium chlorate(I), NaOCl, sodium chloride and water.
Write the balanced equation for this reaction.
(3)
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*(d) Sulfur is an impurity in some fossil fuels.
Explain how the presence of sulfur in fossil fuels can lead to damage to the environment and how the amount of damage can be reduced.
(6)
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Q5.
 
Iron is extracted from iron oxide, Fe2O3.
In the extraction process the iron oxide is heated with carbon to form iron and carbon dioxide.
Write the balanced equation for this reaction.
(3)
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Q6.

(a) Hydrochloric acid can be electrolysed using this apparatus.

     (i) State the form of energy used to carry out the electrolysis.
(1)
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     (ii) Chlorine gas is formed at one electrode.
      Name the gas formed at the other electrode.
(1)
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     (iii) Describe the test to show that a gas is chlorine.
(2)
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(b) Which of these can be used to obtain chlorine from sea water?
      Put a cross (  ) in the box next to your answer.
(1)
    A   corrosion
    B   electrolysis
    C   fractional distillation
    D   neutralisation
(c) Acids react with metal carbonates.
     Complete the word equation for this type of reaction.
(1)
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(d) Acids also react with metal oxides.
Complete and balance the equation for the reaction between copper oxide, CuO, and dilute hydrochloric acid, HCl.
(2)
CuO + . . . . . . . . . . . HCl → CuCl2 + . . . . . . . . . . . . . . . . . . . . . . 
(Total for Question is 8 marks)

Q7.

 If calcium carbonate is heated strongly it decomposes to calcium oxide and carbon dioxide.
Write the balanced equation for this reaction.
(2)
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Q8.

     Metal oxides react with acids to produce salts and water.
      Dilute sulfuric acid was added to magnesium oxide.
      State the name of the salt formed.
(1)
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Q9.

      Methane burns in oxygen to form carbon dioxide and water.
      Write the balanced equation for this reaction.
(3)
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Q10.
 
An atom of copper has an atomic number of 29 and a mass number of 63.
(i)  Complete the table to show the numbers of protons, neutrons and electrons in this atom of copper.
(2)

(ii)  Copper is in period 4 of the periodic table.
State what information this gives about the number of shells that contain electrons, in a copper atom.
(1)
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(iii)  Copper exists as isotopes.
Explain what is meant by the term isotopes.
(2)
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(iv)  A sample of copper contains
70% of copper-63 atoms and
30% of copper-65 atoms.
Use this information to calculate the relative atomic mass of copper in this sample.
(3)
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relative atomic mass of copper = ...........................................................

Q11.
 
When sodium hydroxide solution is mixed with a solution containing copper ions, Cu2+, copper hydroxide, Cu(OH)2, is formed.
(i)  Describe what you would see when these solutions are mixed.
(2)

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(ii)  Write the ionic equation for this reaction.

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(3)

Q12.
 
The concentration of a solution of an alkali can be determined by titration with an acid.
25.0 cm3 portions of the solution of the alkali are transferred into a conical flask and titrated with the acid solution, using a suitable indicator.
(i)  Describe how you would measure out and transfer 25.0 cm3 of the solution of the alkali.
(2)
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(ii)  Complete the sentence by putting a cross () in the box next to your answer.
The burette readings of acid added were

The volume of acid added that should be used in the calculation is
(1)
   A    24.90 cm3
   B    25.00 cm3
   C    25.10 cm3
   D    25.20 cm3

 

Q13.
 
A solution is made by dissolving calcium chloride in water.
11.1 g of calcium chloride are dissolved in water.
The volume of the solution is made up to 500 cm3.
Calculate the concentration, in mol dm−3, of calcium chloride, CaCl2, in this solution.
(relative atomic masses: Cl = 35.5, Ca = 40.0)
(3)
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concentration = ...........................................................mol dm−3