Hydroxyl ion concentration of 10-2 M HCl is
1 × 101 mol dm-3
1 × 10-12 mol dm-3
1 × 10-1 mol dm-3
1 × 10-14 mol dm-3
Which one of the following salts on being dissolved in water gives pH > 7 at 25°C?
KCN
KNO3
NH4Cl
NH4CN
Three moles of PCl3 three moles of PCl3, and two moles of Cl, are taken in a closed vessel. If at equilibrium the vessel has 1.5 moles of PCl5 the number of moles of PCl3, present in it is
5
3
6
4.5
N2 + 3H2 2NH3 + heat.What is the effect of the increase of temperature on the equilibrium of the reaction?
Equilibrium is shifted to the left
Equtlibriumis shifted to the right
Equilibrium is unaltered
Reaction rate does not change
A.
Equilibrium is shifted to the left
N2 + 3H2 2NH3 + heat
It is an exothermic reaction, so high temperature favours backward reaction. Hence, equilibnum is shifted towards the left.
30 cc of , 20 cc of HNO3 and 40 cc of NaOH solutions are mixed and the volume was made up to 1 dm3. The pH of the resulting solution is
8
2
1
3
10-6 M NaOH is diluted 100 times. The pH of the diluted base is
between 7 and 8
between 5 and 6
between 6 and 7
between 10 and 11
2HI (g) H2 (g) + I2 (g)
The equilibrium constant of the above reaction is 6.4 at 300 K. If 0.25 mole each of H2 and I2 are added to the system, the equilibrium constant will be
6.4
0.8
3.2
1.6