Two solutions A and B are prepared by dissolving 1 g of non-volatile solutes X and Y, respectively in 1 kg of water. The ratio of depression in freezing points for A and B is found to be 1 : 4. The ratio of molar masses of X and Y is

Boiling point of a $$2\%$$ aqueous solution of a non-volatile solute A is equal to the boiling point of $$8\%$$ aqueous solution of a non-volatile solute B. The relation between molecular weights of A and B is

4.0 moles of argon and 5.0 moles of PCl5 are introduced into an evacuated flask of 100 litre capacity at 610 K. The system is allowed to equilibrate. At equilibrium, the total pressure of mixture was found to be 6.0 atm. The Kp for the reaction is : [Given : R = 0.082 L atm K$$-$$1 mol$$-$$1]

For a reaction at equilibrium A(g) $$\rightleftharpoons$$ B(g) + {1 \over 2} C(g) the relation between dissociation constant (K), degree of dissociation ($$\alpha$$) and equilibrium pressure (p) is given by :

The equilibrium constant for the reversible reaction 2A(g) $$\rightleftharpoons$$ 2B(g) + C(g) is K1 {3 \over 2}A(g) $$\rightleftharpoons$$ {3 \over 2}B(g) + {3 \over 4}C(g) is K2. K1 and K2 are related as :

The acid that is believed to be mainly responsible for the damage of Taj Mahal is :

Correct statement about photo-chemical smog is :

On the surface of polar stratospheric clouds, hydrolysis of chlorine nitrite gives A and B while its reaction with its reaction with HCl produces B and C. A, B and C are, respectively :

Given below are two Statements: Statement I : Classical smog occurs in cool humid climate. It is a reducing mixture of smoke, fog and sulphur dioxide. Statement II : Photochemical smog has components, ozone, nitric oxide, acrolein, formaldehyde, PAN etc. In the light of the above statements, choose the most appropriate answer from the options given below.

Polar stratospheric clouds facilitate the formation of :

The measured BOD values for four different water samples (A-D) are as follows: A = 3 ppm; B = 18 ppm; C = 21 ppm; D = 4 ppm. The water samples which can be called as highly polluted with organic wastes, are :

Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Polluted water may have a value of BOD of the order of 17 ppm. Reason R : BOD is a measure of oxygen required to oxidise both the bio-degradable an non-biodegradable organic material in water. In the light of the above statements, choose the most appropriate answer from the options given below.

The eutrophication of water body results in :

Some gases are responsible for heating of atmosphere (green house effect). Identify from the following the gaseous species which does not cause it.

The photochemical smog does not generally contain :

Match List I with List II. .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; overflow:hidden;padding:10px 5px;word-break:normal;} .tg th{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; font-weight:normal;overflow:hidden;padding:10px 5px;word-break:normal;} .tg .tg-7btt{border-color:inherit;font-weight:bold;text-align:center;vertical-align:top} .tg .tg-0pky{border-color:inherit;text-align:left;vertical-align:top} List I Pollutant List II Source (A) Microorganisms (I) Strip mining (B) Plant nutrients (II) Domestic sewage (C) Toxic heavy metals (III) Chemical fertilizer (D) Sediment (IV) Chemical factory Choose the correct answer from the options given below :

Match List I with List II. .tg {border-collapse:collapse;border-spacing:0;} .tg td{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; overflow:hidden;padding:10px 5px;word-break:normal;} .tg th{border-color:black;border-style:solid;border-width:1px;font-family:Arial, sans-serif;font-size:14px; font-weight:normal;overflow:hidden;padding:10px 5px;word-break:normal;} .tg .tg-7btt{border-color:inherit;font-weight:bold;text-align:center;vertical-align:top} .tg .tg-0pky{border-color:inherit;text-align:left;vertical-align:top} List I Pollutant List II Disease/sickness (A) Sulphate (>500 ppm) (I) Methemoglobinemia (B) Nitrate (>50 ppm) (II) Brown mottling of teeth (C) Lead (>50 ppb) (III) Laxative effect (D) Fluoride (>2 ppm) (IV) Kidney damage Choose the correct answer from the options given below :

Given below are two statements: Statement I : The non bio-degradable fly ash and slag from steel industry can be used by cement industry. Statement II : The fuel obtained from plastic waste is lead free. In the light of the above statements, choose the most appropriate answer from the options given below :

Given below are two statements: Statement I : In polluted water values of both dissolved oxygen and $$\mathrm{BOD}$$ are very low. Statement II : Eutrophication results in decrease in the amount of dissolved oxygen. In the light of the above statements, choose the most appropriate answer from the options given below :

Which among the following pairs has only herbicides?