4 (a) Which of the following does not conduct electricity?
Put a cross (X) in the box next to your answer - Edexcel - GCSE Chemistry - Question 4 - 2016 - Paper 1
Question 4
4 (a) Which of the following does not conduct electricity?
Put a cross (X) in the box next to your answer.
A sodium chloride crystals
B sodium chloride solution ... show full transcript
Worked Solution & Example Answer:4 (a) Which of the following does not conduct electricity?
Put a cross (X) in the box next to your answer - Edexcel - GCSE Chemistry - Question 4 - 2016 - Paper 1
Step 1
Which of the following does not conduct electricity?
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The option that does not conduct electricity is A sodium chloride crystals. In solid form, sodium chloride does not allow the free movement of ions, which are required for conducting electricity.
Step 2
Describe the use of this apparatus to purify a piece of impure copper.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The apparatus shown is used for the electrolysis of impure copper. During the process:
The impure copper is connected to the anode, and as the current passes through the circuit, copper ions from the anode dissolve into the electrolyte solution.
At the cathode, copper ions in the solution are reduced and deposit on the cathode as pure copper.
Impurities, which do not dissolve, either stay at the anode or form a sludge at the bottom of the electrolytic cell, thus allowing the extraction of pure copper from the impure sample.