A concentrated solution of copper sulphate, which is dark blue in colour, a mixed at room temperature with a
dilute solution of copper sulphate, which is light blue. For this process-
(A) Entropy change is positive, but enthalpy change is negative
(B) Entropy and enthalpy changes are both positive
(C) Entropy change is positive and enthalpy does not change
(D) Entropy change is negative and enthalpy change is positive
Athletes often experience muscle cramps. Which of the following statements is true muscle cramps ?
(A) Muscle cramp is caused due to conversion of pyruvic acid into lactic acid in the cytoplasm
(B) Muscle cramp is caused due to conversion of pyruvic acid into lactic acid in the mitochondria
(C) Muscle cramp is caused due to nonconversion of glucose to pyruvate in the cytoplasm
(D) Muscle cramp is caused due to conversion of pyruvic acid into ethanol in the cytoplasm
150 g of ice is mixed with 100 g of water at temperature 80 oC. The latent heat of ice is 80 cal/g and the specific heat of water is 1 cal/gC. Assuming no heat loss to the environment, the amount of ice which does not melt is
option
(A) 100 g
(B) 0 g
(C) 150 g
(D) 50 g
A solution containing 8.0 g of nicotine in 92 g of water freezes 0.925 degrees below the normal freezing
point of water. If the molal freezing point depression constant Kf = – 1.85ºC mol–1 then the molar mass of
nicotine is-
(A) 16 (B) 80 (C) 320 (D) 160