Ozone is present as a chief constituent in which region of the atmosphere?

• Troposphere

• Stratosphere

• Mesosphere

• Thermosphere

The gas leaked from a storage tank of the Union Carbide plant in Bhopal tragedy was

• Methyl isocyanate

• Methylamine

• Ammonia

• Ammonia

A water sample has ppm level concentration of following anions

F^-= 10; SO₄^2- =100; NO₃^-= 50

the anion/anions that make/makes the water sample unsuitable for drinking is /are:

• only NO₃^-

• both 2 SO₄^- and NO₃^-

• only F^– 

• only F^– 

4.

Identify the wrong statements in the following:

• Chlorofluorocarbons are responsible for ozone layer depletion

• Greenhouse effect is responsible for global warming

• Ozone layer does not permit infrared radiation from the sun to reach the earth

• Ozone layer does not permit infrared radiation from the sun to reach the earth

The smog is essentially caused by the presence of

• O₂ and O₃

• O₃ and N₂

• Oxides of sulphur and nitrogen

• Oxides of sulphur and nitrogen

The recommended concentration of fluoride ion in drinking water is up to 1 ppm as fluoride ion is required to make teeth enamel harder by converting [3Ca₃ (PO4)2.Ca(OH)_2] to

• [3{Ca(OH)₂}. CaF₂]

• [CaF₂]

• [3(CaF₂). Ca(OH)₂]

• [3Ca₃(PO₄)₂. CaF₂]

Among the following, the one which is not a "green house gas", is

• N₂O

• CO₂

• CH₄

• O₂

Metal ion responsible for the Minimata disease is

• Co²⁺

• Hg²⁺

• Cu²⁺

• Zn²⁺

The ozone layer forms naturally by

• the interaction of CFC with oxygen

• the interaction of UV radiation with oxygen

• the interaction of IR radiation with oxygen

• the interaction of oxygen and water vapour

The chemical entities present in thermosphere of the atmosphere are

• ${\mathrm{O}}_2^{+}, {\mathrm{O}}^{+}, {\mathrm{NO}}^{+}$

• O₃

• ${\mathrm{N}}_2, {\mathrm{O}}_2, {\mathrm{CO}}_2, {\mathrm{H}}_2\mathrm{O}$

• ${\mathrm{O}}_3, {\mathrm{O}}_2^{+}, {\mathrm{O}}_2$