Question

Match the items of Column I with the items of Column II.​

Column - I	Column - II
a. Large crystals​	i. Turns lime water milky​
b. Depositing a layer of zinc on iron​	ii. Physical change​
c. Souring of milk​	iii. Rust​
d. Carbon dioxide​	iv. Carbon dioxide​
e. Iron oxide​	v. Chemical change​
f. Dissolving common salt in water​	vi. Galvanisation​

• A. a - iv, b - vi, c - v, d - i, e - iii, f - ii
• B. i

Answer 1

The correct option is A a - iv, b - vi, c - v, d - i, e - iii, f - ii

(a) Large crystals - (iv)​
Sugar candy (Mishri) exists in a large crystal form.​
(b) Depositing a layer of zinc on iron - (vi)​
Galvanisation is the process of depositing a layer of zinc on iron, to prevent iron from rusting.​
(c) Souring of milk - (v)​
Souring of milk is a chemical change as chemical characteristics like taste of milk changes which can not be reversed back.​
(d) Carbon dioxide - (i)​
Carbon dioxide turns lime water milky.​
$C{O}_2$ + Lime water $\left[Ca\right(OH{)}_2]$
$\to$ Calcium Carbonate $CaC{O}_3$ [white]
$\to$ Water $\left(H_{2}O\right)$
​(e) Iron oxide - (iii)​
Iron on exposure to moisture and air, forms iron oxide also known as rust.​
(f) Dissolving common salt in water - (ii)​
Dissolving common salt in water is a physical change which can be reversed to obtain the salt back.​