For a gaseous reaction,
C2H4 + H2 C2H6 ; H = -32.7 Kcal.
The concentration of C2H4 can be decreased by :
increasing pressure
increasing amount of H2
decreasing temperature
all of these
PCl5 was heated in a 10 dm3 container at 250°C
PCl5(g) PCl3(g) + Cl2 (g)
0.1 mol PCl5 and 0.2 mol Cl2 was found at equilibrium. The equilibrium constant for the reaction is :
0.025
0.04
0.02
0.05
At 80°C, distilled water has H+ ions concentration equal to 1 x 10-6 mole/litre. The value of KW at this temperature will be :
1 X 10-6
1 X 10-12
1 X 10-9
1 X 10-15
The pH of solution containing 0.10 M sodium acetate and 0.03 M acetic acid is :
(pKa for CH3COOH = 4.57)
4.09
6.09
5.09
7.09
The solubility of CuBr is 2 x 10-4 mol/L at 25°C. The KSP value for CuBr is :
4 x 10-8 mol2 L-2
4 x 10-4 mol2 L-2
4 x 10-11 mol2 L-2
4 x 10-15 mol2 L-2
In which of the following acid-base titration, pH is greater than 8 at equivalence point?
Acetic acid versus ammonia
Acetic acid versus sodium hydroxide
Hydrochloric acid versus ammonia
Hydrochloric acid versus sodium hydroxide
B.
Acetic acid versus sodium hydroxide
In acetic acid versus sodium hydroxide titration, pH will be greater than 8 at quivalence point because acetic acid ia a weak acid while sodium hydroxide is a strong base. Therefore, at the equivalent point, there will be enough hydroxide ions left.