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 |
Which of the following are Lewis acids?
BCl3 and AlCl3
PH3 and BCl3
AlCl3 and SiCl4
PH3 and SiCl4
A.
BCl3 and AlCl3
Both BCl3 and AlCl3 are Lewis acids as both ‘B’ and ‘Al’ has vacant p-orbitals. SiCl4 is also a Lewis acid as silicon atom has vacant 3d-orbital.
Dissolving NaCN in de-ionised water will result in a solution having
pH < 7
pH = 7
pOH = 7
pH > 7