Which of the following can act as Lowry-Bronsted acid as well as a base ?

1. CI${}^{-}$

2. HCO${}_3^{-}$

3. H${}_3$O+

4. SO${}_4^{2-}$

In the reaction HCN + H${}_2$O $\rightleftharpoons <mspace\; width="1em"></mspace>H_3{O}^{+}+<mspace\; width="1em"></mspace>C{N}^{-}$ the conjugate acid- base pair is 

1. HCN,H${}_3$O${}^{+}$

2. HCN,CN${}^{-}$

3. $H_{2}O,<mspace\; width="1em"></mspace>C{N}^{-}$

4. $C{N}^{-},H_3{O}^{+}$

At a certain temperature the following equilibrium is established, CO(g) + N0₂(g) $\stackrel{}{\rightleftharpoons }$ CO₂(g)+ NO(g)One mole of each of the four gas is mixed in one litre container and the reaction is allowed to reach equilibrium state. When excess of baryta water (Ba(OH)₂) is added to the equilibrium mixture, the weight of white ppt (BaCO₃) obtained is 236.4 gm. The equilibrium constant K_c of the reaction is (Ba = 137)

(1) 1.2

(2) 2.25

(3) 2.1

(4) 3.6

The pH of 0.1 M solution of the following slats increases in the order 

1. NaCl < NH${}_4$Cl < NaCN < HCl 

2. HCl < NH${}_4$Cl < NaCl < NaCN

3. NaCN < NH${}_4$Cl < NaCl <HCl 

4. HCl < NaCl < NaCN < NH${}_4$Cl

The solubility product of CuS, Ag${}_2$S. HgS are 10${}^{-37},{10}^{-44}$ and 10${}^{-54}$ respectively. The solubilities of these sulphides are in the order of: 

1. Ag${}_2$S > CuS > HgS

2. Ag${}_2$S > HgS > CuS

3. HgS > Ag${}_2$S > CuS

4. CuS > Ag${}_2$S > HgS 

In which of the following solvents will AgBr have the highest solubility 

1. 10${}^{-3}$ M NaBr

2. 10${}^{-3}$ M NH4OH 

3. Pure water 

4. 10${}^{-3}$ M HBr

40 mg of pure sodium hydroxide is dissolved in 10 litres of distilled water. The pH of the

solution is 

1. 9.0

2. 10

3. 11

4. 12

A monoprotic acid in a 0.1 M solution ionizes to 0.001%.Its ionisation constant is 

1. $1.0 \times {10}^{-3}$

2. $1.0 \times {10}^{-6}$

3.$1.0 \times {10}^{-8}$

4. $1.0 \times {10}^{-11}$

With increase in temperature, ionic product of water 

1. decreases 

2. increases 

3. remains same 

4. may increase or decrease 

pH of pure water at 25$°$C is 7 . If water is heated to 60 $°$C, the 

1. pH will decrease 

2. pH will increase 

3. pH will remain constant 

4. H${}^{+}$ions and OH${}^{-}$ions concentrations will become unequal.