4 (a) A solution of sodium chloride can be decomposed using electrolysis - Edexcel - GCSE Chemistry - Question 4 - 2018 - Paper 1
Question 4
4 (a) A solution of sodium chloride can be decomposed using electrolysis. The products formed at the electrodes are chlorine gas and hydrogen gas.
(i) State the for... show full transcript
Worked Solution & Example Answer:4 (a) A solution of sodium chloride can be decomposed using electrolysis - Edexcel - GCSE Chemistry - Question 4 - 2018 - Paper 1
Step 1
State the form of energy used to carry out the electrolysis.
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Answer
The form of energy used to carry out the electrolysis is electrical energy or electricity. This energy is necessary to drive the non-spontaneous chemical reaction.
Step 2
Describe a test to show that the gas is chlorine.
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Answer
To test for chlorine gas, you can use moist blue litmus paper. When chlorine gas comes into contact with the paper, it bleaches it and turns it white. If the litmus paper does not change color, then the gas is not chlorine.
Step 3
Which of these is made using chlorine?
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Answer
A bleach
(B) cement
(C) glass
(D) poly(ethene)
You should put a cross (X) in box A next to 'bleach' as it is made using chlorine.
