Arrhenius Bases

Q.

Bases when dissolved in water produce_______

Q. Mention the ions which cause temporary and permanent hardness of water

Q. Formic acid is $4.5\%$ dissociated in a $0.1\text{N}$ solution at ${20}^{\circ }\text{C}$. The ionization constant of formic acid is:

1. $21\times {10}^{-4}$
2. $21$
3. $0.21\times {10}^{-4}$
4. $2.1\times {10}^{-4}$

Q.

Give examples of a base.

Q. Which of the following compounds is the best proton acceptor?

1. Ethanol
2. Phenol
3. p-Cresol
4. p-Nitrophenol

Q. Which of the following is a Bronsted acid?
$\left(i\right)HCN\left(ii\right)H_{2}P{O}_4^{-}\left(iii\right)S{O}_4^{2-}\left(iv\right)N{H}_3$

1. $\left(i\right),\left(ii\right)$
2. $\left(i\right),\left(iii\right)$
3. $\left(iii\right),\left(iv\right)$
4. $\left(ii\right),\left(iv\right)$

Q.

Why does a base fail to show basic behavior in absence of water?

Q.

Name:

A water soluble base.

Q.

Which of the following is the best acceptor of proton ?

1. OH^‑

2. O^‑2

3. CH₃^-

4. NH₃

Q. Which is the strongest base?

1. $NaOH$
2. $Mg(OH{)}_2$
3. $N{H}_{4}OH$
4. None of these

Q.

HOW TO SAY IF A COMPOUND IS GIVEN AND IT IS ALKALINE OR BASIC

Q. $KOH\to$

1. $K^{+}\left(aq\right)+O{H}^{-}\left(aq\right)$
2. $K^{+}\left(aq\right)+2O{H}^{-}\left(aq\right)$
3. $K^{+}\left(aq\right)+O{H}^{-}\left(aq\right)+H^{+}$
4. All of the above

Q. Ammonium hydroxide is said to be a weak base because

1. It has low vapour pressure
2. It is slightly ionised
3. It has low density
4. It is not a hydroxide of any metal

Q.

which is stronger base naoh and koh.explain

Q. If the strong base is dissolved in water ___________.

1. less number of hydroxide ions produced by base in water.
2. equal number of hydroxide ions produced by base in water.
3. more number of hydroxide ions produced by base in water.
4. none of these

Q.

Which of the following is the best acceptor of proton ?

1. ${OH}^{-}$

2. $O^{-2}$

3. ${C{H}_3}^{-}$

4. $N{H}_3$

Q. Soluble bases are called:

1. salts
2. acids
3. alkalis
4. all the above

Q. Ammonium hydroxide is said to be a weak base because

1. It has low vapour pressure
2. It has low density
3. It is slightly ionised
4. It is not a hydroxide of any metal

Q. All bases are soluble in water.

1. True
2. False

Q. A solution containing 1.23 g of $Ca(N{O}_3{)}_2$ in 10 g of water boils at $100-{97}^{o}C$. Calculate degree of ionisation of the nitrate ($K_b=0\cdot 52$).

Q.
In order to study saponification reaction we first prepare 20% solution of sodium hydroxide. If we record the temperature of this solution just after adding sodium hydroxide flakes to water and also test its nature using litmus, it may be concluded that the process of making this solution is :

1. exothermic and the solution is alkaline
2. endothermic and the solution is alkaline
3. endothermic and the solution is acidic
4. exothermic and the solution is acidic

Q. $p{K}_a$ of Quinoline base is 4.88 .What will be the $p{K}_a$ of 0.01 M solution of it?

1. 4.88
2. 0.01
3. 9.12
4. 14

Q. When base dissolves in water, it should dissociate to form:

1. hydroxide ions
2. all of the above
3. carbide ions
4. potassium ions

Q. Give one example is a hydroxide which is insoluble in water.

Q. Consider the $M(OH{)}_3$ formed by all the group 13 elements. The correct sequence of acidic strength of hydroxides $\left[M\right(OH{)}_3]$ is:-

1. $B(OH{)}_3<Al(OH{)}_3>Ga(OH{)}_3>In(OH{)}_3>Tl(OH{)}_3$
2. $B(OH{)}_3>Tl(OH{)}_3>Al(OH{)}_3>In(OH{)}_3>Ga(OH{)}_3$
3. $Al(OH{)}_3>Ga(OH{)}_3>B(OH{)}_3>In(OH{)}_3>Tl(OH{)}_3$
4. $B(OH{)}_3>Al(OH{)}_3>Ga(OH{)}_3>In(OH{)}_3>Tl(OH{)}_3$

Q. Give one example of a basic oxide which is soluble in water.