6.When helium gas is allowed to expand into Vaccum, a heating effect is observed. The reason for this is (assume He as a non-ideal gas) A) He is an inert gas B) The inversion temperature of helium is very high C) The inversion temperature of helium is very low D) He has the lowest boiling point View Answer Report DiscussAnswer: Option CExplanation:Hydrogen and helium exhibit heating effects during Joule Thomson expansion due to low inversion temperature.
7.Which of the following element is purified by vapour phase refining? A) Fe B) Zr C) Cu D) Au View Answer Report DiscussAnswer: Option BExplanation:Van Arkel method for refining Zr, Ti and Mond's process for Ni on vapour phase refining methods
8.Balance the following equation by choosing the correct option . $xKNO_{3}+yC_{12}H_{22}O_{11} \rightarrow pN_{2}+qCO_{2}+rH_{2}O+sK_{2}CO_{3}$ A) x:36,y=55,p:24,q=24,r=5,s=48 B) x=48,y=5,p=24,q=36,r=55,s=24 C) x=24,y=24,p=36,q=55,r=48,s=5 D) x=24,y=48, p=36,q=24,r=5,s=55 View Answer Report DiscussAnswer: Option BExplanation:$48 KNO_{3}+5C_{12}H_{22}O_{11} \rightarrow 24 N_{2}+36 CO_{2}+55H_{2}O+24 K_{2}CO_{3}$
9.Standard enthalpy (heat) of formation of liquid water at $25^{0}C$ is around $H_{2} (g)+\frac{1}{2} O_{2}(g) \rightarrow H_{2} O(l) $ A) -237 kJ/mol B) 237 kJ/mol C) -286 kJ/mol D) 286 kJ/mol View Answer Report DiscussAnswer: Option CExplanation:$(\triangle H_{f}^{0})_{water}$ =-286 kJ/mol
10............... is a potent vasodilator A) Histamine B) Serotonin C) Codeine D) Cimetidine View Answer Report DiscussAnswer: Option AExplanation:Histamine is a potent vasodilator