Question
Write short notes on the following: Tinning.
✓
Answer
The process of coating a thin layer of tin (molten tin) on copper or brass is called tinning. Cooking vessels made of copper and brass get a greenish coating due to corrosion. The greenish substance is copper carbonate and it is poisonous. If buttermilk or curry is placed in such a vessel it gets spoiled. Therefore, these vessels are coated with tin to prevent corrosion.
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(i) What is the atomic number of this element?
(ii) What is the group of this element?
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(The letters given here are not the chemical symbols of the elements):
(The letters given here are not the chemical symbols of the elements):
|
a
3
|
b
4
|
|
c
5
|
d
6
|
e
7
|
f
8
|
g
9
|
h
10
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|
i
11
|
j
12
|
|
k
13
|
l
14
|
m
15
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n
16
|
o
17
|
p
18
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