Chemistry - Study Mode

[#126] Which one of the following is found in kidney stones?
Correct Answer

(B) Calcium oxalate

Explanation

Solution: The most common type of kidney stone is a calcium oxalate stone. These result when the urine contains low levels of citrate and high levels of calcium and either oxalate or uric acid. Calcium oxalate stones are linked with foods high in oxalate, which is a naturally occurring substance in plants and animals.

[#127] Which one of the following is not present in cement ?
Correct Answer

(C) Alum

Explanation

Solution: Gypsum is added in calculated quantity in order to adjust the rate of setting of cement. Alum is not present in cement.

[#128] Activated Charcoal is used to remove colouring matter from pure substances by
Correct Answer

(C) Adsorption

Explanation

Solution: Activated charcoal is used to remove colouring matter from pure substances. It works by adsorption. Colour impurities are adsorbed on the surface of activated charcoal.

[#129] The molecular mass of a gas is
Correct Answer

(A) Twice its vapour pressure

Explanation

Solution: The molecular mass of a gas is twice its vapour pressure.

[#130] The value of gas constant R in Ergs deg –1 mole –1 is
Correct Answer

(A) 8.314 × 10 7

Explanation

Solution: The universal gas constant R signifies the work done by or on a gas per mole per kelvin. The SI unit of R is J mole -1 K -1 and its value is 8.314 J mole -1 K -1 . In CGS unit, the value of R is 1.98 cal mol -1 °C -1 .