Tag: reactions of acids and bases

Questions Related to reactions of acids and bases

Ist & IInd dissociation const. for oxalic acid is $K _{1}$  and $K _{2}$  which is right statement is : 

  1. $K _{2}$ ,$K _{1}$ are equal

  2. $K _{2}$ is 1000 times greater thean $K _{1}$

  3. $K _{2}$ is $\frac{1}{1000}$ time than $K _{1}$

  4. All correct


Correct Option: C

The main constituent of bio-gas is:-

  1. $ CH _4 $

  2. $ CO _2 $

  3. $ H _2 S $

  4. $ H _2 $


Correct Option: A

When a metal carbonate is treated with dilute hydrochloric acid, the gas liberated is:

  1. hydrogen

  2. chlorine

  3. carbon monoxide

  4. carbon dioxide


Correct Option: D
Explanation:

When metal carbonate is treated with dilute hydrochloric acid, the products formed are salt, water and carbon dioxide.

This is a type of neutralization reaction but here an intermediate called as carbonic acid is formed $H _2CO _3$, but it gets split into salt, water and carbon dioxide $(CO _2)$, as the intermediate is unstable.
$CO _2$ gas that is produced causes effervescence or bubbling.
Thus, the correct answer is option (D).

The metal carbonate will form bubbles giving off carbon dioxide gas and the other products namely :

  1. salt and water

  2. water and heat

  3. water and gas

  4. salt and gas


Correct Option: A

Acids liberate sulphur dioxide with metallic sulphides.

  1. True

  2. False


Correct Option: A
Explanation:

Acids liberate sulphur dioxide or hydrogen sulphide on reaction with metallic sulphides.

When are marble chips treated with $HCl$, which of the following gas is liberated?

  1. ${ CO } _{ 2 }$

  2. ${ O } _{ 2 }$

  3. CO

  4. ${ NO } _{ 2 }$


Correct Option: A
Explanation:

Marble chips are made up of by calcium carbonate. When they are treated with $HCl$, carbon dioxide gas is formed along with water and calcium chloride. ${ CaCO } _{ 3 }+HCl\rightarrow { CaCl } _{ 2 }+{ H } _{ 2 }O+{ CO } _{ 2 }$

Metal carbonates and hydrogen carbonates react with acids to give :

  1. carbon dioxide gas

  2. hydrogen gas

  3. sulphur dioxide gas

  4. carbon monoxide gas


Correct Option: A
Explanation:

Carbonates contain carboxylate ion which reacts with mineral acids to form carbon dioxide gas which gets evolved from the reaction mixture.

The strongest base among the following is:

  1. $CH^{-} _{3}$

  2. $F^{-}$

  3. $NH^{-} _{2}$

  4. $OH^{-}$


Correct Option: A
Explanation:

${CH _3}^-$ is an extremely strong base because it is the conjugate base of weak acid $CH _4$.

When $KHSO _{4}$ is added to concentrated solution of $H _{2}SO _{4}$, the acidity of the solution ?

  1. Increases

  2. Decreases

  3. Remains constant

  4. Can't be predicted


Correct Option: C
Explanation:

When $KHSO _4$ is added to concentrated $H _2SO _4$, the acidity remains constant.

Because $H _2SO _4$ is highly concentrated, it's acidity won't increase by adding $KHSO _4$ .

The weakest Lewis base ?

  1. $ H^- $

  2. $OH^- $

  3. $ CI^- $

  4. $ HCO _3^- $


Correct Option: C
Explanation:

Lewis base is a compound that should donate electrons easily.

The weakest Lewis base is $Cl^{\circleddash}$, because it has octet rule. $Cl^{\circleddash}$ won't donate electrons easily.