Which one of the following gases is placed second in respect of abundance in the Earth's atmosphere? |
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(a) |
Oxygen |
(b) |
Hydrogen |
(c) |
Nitrogen |
(d) |
Carbon dioxide |
Which one of the following gases is placed second in respect of abundance in the Earth's atmosphere? |
|||
(a) |
Oxygen |
(b) |
Hydrogen |
(c) |
Nitrogen |
(d) |
Carbon dioxide |