Tardigrade
Tardigrade - CET NEET JEE Exam App
Exams
Login
Signup
Tardigrade
Question
Chemistry
Calcium is tarnished in air, because it is covered with a thin film of
Q. Calcium is tarnished in air, because it is covered with a thin film of
1956
145
NTA Abhyas
NTA Abhyas 2020
The s-Block Elements
Report Error
A
oxide
75%
B
hydroxide
0%
C
carbonate
19%
D
basic carbonate
6%
Solution:
Calcium is tarnished in air, because it is covered with a thin film of oxide.
C
a
+
O
2
→
2
C
a
O
In moist air, it is slowly tarnished, but decomposes water fairly rapidly giving hydrogen.
C
a
+
2
H
2
O
→
C
a
(
O
H
)
2
+
H
2