Among the following acids which has the lowest pKa value?
CH3COOH
HCOOH
(CH3)2COOH
(CH3)2COOH
What is the equilibrium expression for the reaction P4(s) +5O2(g)⇌ P4O10(s)?
Kc = [P4O10] / P4] [O2]5
Kc = 1/[O2]5
Kc = [O2] 5
Kc = [O2] 5
The equilibrium constant for the reaction N2(g) + O2(g) ⇌ 2NO(g) at temperature T is 4×10-4. The value of Kc for the reaction NO(g) ⇌ 1/2N2(g) + 1/2O2(g) at the same temperature.
2.5×102
0.02
4 x 10-4
4 x 10-4
An alkali is titrated against an acid with methyl orange as indicator, which of the following is a correct combination?
Base | Acid | End Point |
Strong | Strong | Pink to colourless |
Base | Acid | End Point |
Weak | Strong | Colourless to pink |
Base | Acid | End Point |
Strong | Strong | Pinkish Red to Yellow |
Base | Acid | End Point |
Weak | Strong | Yellow to Pinkish Red |
D.
Base | Acid | End Point |
Weak | Strong | Yellow to Pinkish Red |
Methyl orange is the weak organic base. It is used in the titration of WB vs SA
In a basic medium, equilibrium lies in the backward direction and therefore it shows yellow colour.
In acidic medium, equilibrium shifts in forwarding direction and therefore, colour changes from yellow to red.
Which of the following are Lewis acids?
BCl3 and AlCl3
PH3 and BCl3
AlCl3 and SiCl4
PH3 and SiCl4
Dissolving NaCN in de-ionised water will result in a solution having
pH < 7
pH = 7
pOH = 7
pH > 7