Consider the following reaction H (g) + I, (g) rightarrow 2HI (g) What is AG deg
ID: 867323 • Letter: C
Question
Consider the following reaction H (g) + I, (g) rightarrow 2HI (g) What is AG degree for the reaction at 25 degree C ? -16.0 kJ -6.6 kJ 110 kJ 19.2 kJ If AH 0, then which statement is true The reaction will be always be spontaneous The reaction will only be spontaneous at high temperature The reaction will only be spontaneous at low temperature The reaction will never be spontaneous Consider the following reaction in acidic solution. Se()- (aq) + ClOj (aq) rightyarrow SeOj- (sq) + Cl2, (g) What are the coefficients of SeO and CIOJ in the balanced reaction? 5 Se()|" and 2 CIO3 3 SeOjj and 2 CIO3 2 SeO and 2 CIOJ 2 SeOi" and 3 CIO.7 2 SeO" and 5 CIO3Explanation / Answer
answer : option a) -16.0 kJ
H2 + I2 ---------------> 2HI
delta H = deltaH products - delta H reactants
= 2 x 26.5 -(0+62.4)
= -9.4kJ/mol
delat S= delta S products - delta S reactants
= 2 x207 - (131+ 261)
= 22 J/Kmol
T= 25 + 273 =298 K
from gibbs-helmholtz equation
delat G = delat H -T delat S
= -9.4 - 298 x 22 x10^-3
= -15.96 kJ/mol
delat G = -15.96 kJ/mol =-16kJ
5) answer : option a) the reaction will be always spontaneous
delta G = delta H - T delta S
if delta H =-ve , delta S = +ve then delta G always negative . so the reaction is always spontaneous
6) answer : option a) 5 and 2
5 SeO3{-2} + 2 ClO3{-} + 2 H{+} = 5 SeO4{-2} + Cl2 + H2O