QBManager

CHXI10:THE S-BLOCK ELEMENTS

315972 Sodium peroxide in contact with moist air turns white due to formation of:

1

{Na}_{2} {CO}_{3}

2

{Na}_{2} O

3

NaOH

4

{NaHCO}_{3}

Explanation:

$N a_{2} O_{2} + H_{2} O \to 2 N a O H + \frac{1}{2} O_{2}$

CHXI10:THE S-BLOCK ELEMENTS

315973 ${CO}_{2}$ gas along with solid $(Y)$ is obtained when sodium salt $(X)$ is heated. $(X)$ is again obtained when ${CO}_{2}$ gas is passed into (Y). $X & Y$ are

1

{Na}_{2} {CO}_{3}, {Na}_{2} O

2

{Na}_{2} {CO}_{3}, NaOH

3

{NaHCO}_{3}, {Na}_{2} {CO}_{3}

4

{Na}_{2} {CO}_{3}, {NaHCO}_{3}

Explanation:

$\underset{(X)}{2NaHC O_{3}} \overset{Heat}{\to} \underset{(Y)}{N a_{2} C O_{3}} + H_{2} O + C O_{2}$
$\underset{(Y)}{N a_{2} C O_{3}} + H_{2} O + C O_{2} \to \underset{(X)}{2NaHC O_{3}}$

CHXI10:THE S-BLOCK ELEMENTS

315974 ${Na}_{2} {CO}_{3}$ and ${NaHCO}_{3}$ can be distinguished by treating with

1 litmus solution

2 dil.

H_{2} {SO}_{4}

3

{MgCO}_{3}

4 phenolphthalein

CHXI10:THE S-BLOCK ELEMENTS

315975 Which one of the following statements is incorrect?

1 Pure sodium metal dissolves in liquid ammonia to give blue solution

2

NaOH

reacts with glass to give sodium silicate

3 Aluminium reacts with excess of

NaOH

to give

Al (OH)_{3}

4

{NaHCO}_{3}

on heating gives

{Na}_{2} {CO}_{3}

Explanation:

$Al$ reacts with $NaOH$ to give ${NaAlO}_{2}$

CHXI10:THE S-BLOCK ELEMENTS

315972 Sodium peroxide in contact with moist air turns white due to formation of:

1

{Na}_{2} {CO}_{3}

2

{Na}_{2} O

3

NaOH

4

{NaHCO}_{3}

Explanation:

$N a_{2} O_{2} + H_{2} O \to 2 N a O H + \frac{1}{2} O_{2}$

CHXI10:THE S-BLOCK ELEMENTS

315973 ${CO}_{2}$ gas along with solid $(Y)$ is obtained when sodium salt $(X)$ is heated. $(X)$ is again obtained when ${CO}_{2}$ gas is passed into (Y). $X & Y$ are

1

{Na}_{2} {CO}_{3}, {Na}_{2} O

2

{Na}_{2} {CO}_{3}, NaOH

3

{NaHCO}_{3}, {Na}_{2} {CO}_{3}

4

{Na}_{2} {CO}_{3}, {NaHCO}_{3}

Explanation:

$\underset{(X)}{2NaHC O_{3}} \overset{Heat}{\to} \underset{(Y)}{N a_{2} C O_{3}} + H_{2} O + C O_{2}$
$\underset{(Y)}{N a_{2} C O_{3}} + H_{2} O + C O_{2} \to \underset{(X)}{2NaHC O_{3}}$

CHXI10:THE S-BLOCK ELEMENTS

315974 ${Na}_{2} {CO}_{3}$ and ${NaHCO}_{3}$ can be distinguished by treating with

1 litmus solution

2 dil.

H_{2} {SO}_{4}

3

{MgCO}_{3}

4 phenolphthalein

CHXI10:THE S-BLOCK ELEMENTS

315975 Which one of the following statements is incorrect?

1 Pure sodium metal dissolves in liquid ammonia to give blue solution

2

NaOH

reacts with glass to give sodium silicate

3 Aluminium reacts with excess of

NaOH

to give

Al (OH)_{3}

4

{NaHCO}_{3}

on heating gives

{Na}_{2} {CO}_{3}

Explanation:

$Al$ reacts with $NaOH$ to give ${NaAlO}_{2}$

CHXI10:THE S-BLOCK ELEMENTS

315972 Sodium peroxide in contact with moist air turns white due to formation of:

1

{Na}_{2} {CO}_{3}

2

{Na}_{2} O

3

NaOH

4

{NaHCO}_{3}

Explanation:

$N a_{2} O_{2} + H_{2} O \to 2 N a O H + \frac{1}{2} O_{2}$

CHXI10:THE S-BLOCK ELEMENTS

315973 ${CO}_{2}$ gas along with solid $(Y)$ is obtained when sodium salt $(X)$ is heated. $(X)$ is again obtained when ${CO}_{2}$ gas is passed into (Y). $X & Y$ are

1

{Na}_{2} {CO}_{3}, {Na}_{2} O

2

{Na}_{2} {CO}_{3}, NaOH

3

{NaHCO}_{3}, {Na}_{2} {CO}_{3}

4

{Na}_{2} {CO}_{3}, {NaHCO}_{3}

Explanation:

$\underset{(X)}{2NaHC O_{3}} \overset{Heat}{\to} \underset{(Y)}{N a_{2} C O_{3}} + H_{2} O + C O_{2}$
$\underset{(Y)}{N a_{2} C O_{3}} + H_{2} O + C O_{2} \to \underset{(X)}{2NaHC O_{3}}$

CHXI10:THE S-BLOCK ELEMENTS

315974 ${Na}_{2} {CO}_{3}$ and ${NaHCO}_{3}$ can be distinguished by treating with

1 litmus solution

2 dil.

H_{2} {SO}_{4}

3

{MgCO}_{3}

4 phenolphthalein

CHXI10:THE S-BLOCK ELEMENTS

315975 Which one of the following statements is incorrect?

1 Pure sodium metal dissolves in liquid ammonia to give blue solution

2

NaOH

reacts with glass to give sodium silicate

3 Aluminium reacts with excess of

NaOH

to give

Al (OH)_{3}

4

{NaHCO}_{3}

on heating gives

{Na}_{2} {CO}_{3}

Explanation:

$Al$ reacts with $NaOH$ to give ${NaAlO}_{2}$

CHXI10:THE S-BLOCK ELEMENTS

315972 Sodium peroxide in contact with moist air turns white due to formation of:

1

{Na}_{2} {CO}_{3}

2

{Na}_{2} O

3

NaOH

4

{NaHCO}_{3}

Explanation:

$N a_{2} O_{2} + H_{2} O \to 2 N a O H + \frac{1}{2} O_{2}$

CHXI10:THE S-BLOCK ELEMENTS

315973 ${CO}_{2}$ gas along with solid $(Y)$ is obtained when sodium salt $(X)$ is heated. $(X)$ is again obtained when ${CO}_{2}$ gas is passed into (Y). $X & Y$ are

1

{Na}_{2} {CO}_{3}, {Na}_{2} O

2

{Na}_{2} {CO}_{3}, NaOH

3

{NaHCO}_{3}, {Na}_{2} {CO}_{3}

4

{Na}_{2} {CO}_{3}, {NaHCO}_{3}

Explanation:

$\underset{(X)}{2NaHC O_{3}} \overset{Heat}{\to} \underset{(Y)}{N a_{2} C O_{3}} + H_{2} O + C O_{2}$
$\underset{(Y)}{N a_{2} C O_{3}} + H_{2} O + C O_{2} \to \underset{(X)}{2NaHC O_{3}}$

CHXI10:THE S-BLOCK ELEMENTS

315974 ${Na}_{2} {CO}_{3}$ and ${NaHCO}_{3}$ can be distinguished by treating with

1 litmus solution

2 dil.

H_{2} {SO}_{4}

3

{MgCO}_{3}

4 phenolphthalein

CHXI10:THE S-BLOCK ELEMENTS

315975 Which one of the following statements is incorrect?

1 Pure sodium metal dissolves in liquid ammonia to give blue solution

2

NaOH

reacts with glass to give sodium silicate

3 Aluminium reacts with excess of

NaOH

to give

Al (OH)_{3}

4

{NaHCO}_{3}

on heating gives

{Na}_{2} {CO}_{3}

Explanation:

$Al$ reacts with $NaOH$ to give ${NaAlO}_{2}$