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Chemical Effects of Electric Current — Science STD 8 — Question

Gujarat BoardEnglish MediumSTD 8ScienceChemical Effects of Electric Current4 Marks
Question
Electroplating is the process of adding a surface layer of metal on another metal.Image
$7.$ Which of these is true about electroplating?
Circle ‘Yes’ or ‘No’ for the correct response.
Is the statement true? Yes or No
The solution used contains ions of two metals. Yes/No
Metal gets deposited on the electrode connected to the negative terminal. Yes/No
A non-metal is used as the electrode connected to the positive terminal. Yes/No
$8.$ Which of these is an example of electroplating?
$A.$ Colouring of jeans
$B.$ Painting of a wall
$C.$ Lamination of a photograph
$D.$ Gold plating of imitation jewelleries
$9. $ Sumit replaced all the bulbs in his home with $LEDs.$
After a month, he noticed that the electricity bill had decreased.
What was the most likely reason for the decrease in electricity bill?
$10.$ Distilled water is a bad conductor of electricity.
Why does rainwater conduct electricity?
✓

Answer

$7.$ No
Yes
No
$8. D.$ Gold plating of imitation jewelleries
$9.$ Mentions that $LEDs$ consume less electricity than bulbs.
$10.$ Mentions that rainwater contains dissolved salts that conduct electricity.

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