Water is considered to be polluted if the dissolved oxygen D.O. content is less than .... ppm
5
10
15
100
Identify the correct decreasing order of the following with respect to altitude from atmosphere
I. Troposphere
II. Mesosphere
III. Thermosphere
II, III, I
III, II, I
I, II, III
I, III, II
CFCl3 is responsible for the decomposition of ozone to oxygen. Which of the following reacts with ozone to form oxygen ?
Cl2
Cl-
F-
Cl*
At T (K), 100 L of dry oxygen is present in a sealed container. It is subjected to silent electric discharge, till the volumes of oxygen and ozone become equal. What is the volume (in litres) of ozone formed at T (K) ?
50
60
30
40
Bhopal gas tragedy of 1984 was caused by
carbon monoxide
phosgene
methyl cyanate
methyl isocyanate
Among the following compounds, which one is not responsible for depletion of ozone layer?
CH4
CFCl3
NO
Cl2
A.
CH4
In stratosphere the following reactions takes place which are responsible for depletion of ozone layer:
NO + O3 → NO2 + O2
CF2Cl2 F2Cl +
CFCl3
+ O3 → Cl + O2
Cl + O → + O2
Hence, methane is not responsible for ozone layer depletion.
The chemical entities present in thermosphere of the atmosphere are
O, O+, NO+
O3
N2, O2, CO2, H2O
O3, O, O2