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07. The p-BLOCK ELEMENTS (XII)

189578 Which of the following is not hydrolysed

1

A s C l_{3}

2

P F_{3}

3

S b C l_{3}

4

N F_{3}

Explanation:

(d) Due to absence of $d$ - orbitals in $N$ atom, it cannot accept electrons from $H_{2} O$ for hydrolysis of $N F_{3}$ .

07. The p-BLOCK ELEMENTS (XII)

189579 Electrolysis temperature is maximum for

1

A s H_{3}

2

N H_{3}

3

P H_{3}

4

S b H_{3}

Explanation:

(b) $N H_{3}$ is most thermally stable hydride. Hence, electrolysis temperature is maximum.

07. The p-BLOCK ELEMENTS (XII)

189580 Which of the following is kept in water?

1 White phosphorous

2 Sodium

3 Potassium

4 Calcium

Explanation:

(a)Phosphorus is kept in water due to it burt at $30^{o} C$ .

07. The p-BLOCK ELEMENTS (XII)

189583 $V - A$ group precipitate was dissolved in $H N O_{3}$ and treated with excess of $N H_{4} O H$ . It gives a white ppt. because of

1

C u (O H)_{2}

2

C d (O H)_{2}

3

B i (O H)_{3}

4

H g (O H)_{2}

Explanation:

(c) When the black ppt. of $B i_{2} S_{3}$ is dissolved in $50 %$ $H N O_{3}$ and a solution of $N H_{4} O H$ is added. A white ppt. of $B i (O H)_{3}$ is obtained.

07. The p-BLOCK ELEMENTS (XII)

189578 Which of the following is not hydrolysed

1

A s C l_{3}

2

P F_{3}

3

S b C l_{3}

4

N F_{3}

Explanation:

(d) Due to absence of $d$ - orbitals in $N$ atom, it cannot accept electrons from $H_{2} O$ for hydrolysis of $N F_{3}$ .

07. The p-BLOCK ELEMENTS (XII)

189579 Electrolysis temperature is maximum for

1

A s H_{3}

2

N H_{3}

3

P H_{3}

4

S b H_{3}

Explanation:

(b) $N H_{3}$ is most thermally stable hydride. Hence, electrolysis temperature is maximum.

07. The p-BLOCK ELEMENTS (XII)

189580 Which of the following is kept in water?

1 White phosphorous

2 Sodium

3 Potassium

4 Calcium

Explanation:

(a)Phosphorus is kept in water due to it burt at $30^{o} C$ .

07. The p-BLOCK ELEMENTS (XII)

189583 $V - A$ group precipitate was dissolved in $H N O_{3}$ and treated with excess of $N H_{4} O H$ . It gives a white ppt. because of

1

C u (O H)_{2}

2

C d (O H)_{2}

3

B i (O H)_{3}

4

H g (O H)_{2}

Explanation:

(c) When the black ppt. of $B i_{2} S_{3}$ is dissolved in $50 %$ $H N O_{3}$ and a solution of $N H_{4} O H$ is added. A white ppt. of $B i (O H)_{3}$ is obtained.

07. The p-BLOCK ELEMENTS (XII)

189578 Which of the following is not hydrolysed

1

A s C l_{3}

2

P F_{3}

3

S b C l_{3}

4

N F_{3}

Explanation:

(d) Due to absence of $d$ - orbitals in $N$ atom, it cannot accept electrons from $H_{2} O$ for hydrolysis of $N F_{3}$ .

07. The p-BLOCK ELEMENTS (XII)

189579 Electrolysis temperature is maximum for

1

A s H_{3}

2

N H_{3}

3

P H_{3}

4

S b H_{3}

Explanation:

(b) $N H_{3}$ is most thermally stable hydride. Hence, electrolysis temperature is maximum.

07. The p-BLOCK ELEMENTS (XII)

189580 Which of the following is kept in water?

1 White phosphorous

2 Sodium

3 Potassium

4 Calcium

Explanation:

(a)Phosphorus is kept in water due to it burt at $30^{o} C$ .

07. The p-BLOCK ELEMENTS (XII)

189583 $V - A$ group precipitate was dissolved in $H N O_{3}$ and treated with excess of $N H_{4} O H$ . It gives a white ppt. because of

1

C u (O H)_{2}

2

C d (O H)_{2}

3

B i (O H)_{3}

4

H g (O H)_{2}

Explanation:

(c) When the black ppt. of $B i_{2} S_{3}$ is dissolved in $50 %$ $H N O_{3}$ and a solution of $N H_{4} O H$ is added. A white ppt. of $B i (O H)_{3}$ is obtained.

07. The p-BLOCK ELEMENTS (XII)

189578 Which of the following is not hydrolysed

1

A s C l_{3}

2

P F_{3}

3

S b C l_{3}

4

N F_{3}

Explanation:

(d) Due to absence of $d$ - orbitals in $N$ atom, it cannot accept electrons from $H_{2} O$ for hydrolysis of $N F_{3}$ .

07. The p-BLOCK ELEMENTS (XII)

189579 Electrolysis temperature is maximum for

1

A s H_{3}

2

N H_{3}

3

P H_{3}

4

S b H_{3}

Explanation:

(b) $N H_{3}$ is most thermally stable hydride. Hence, electrolysis temperature is maximum.

07. The p-BLOCK ELEMENTS (XII)

189580 Which of the following is kept in water?

1 White phosphorous

2 Sodium

3 Potassium

4 Calcium

Explanation:

(a)Phosphorus is kept in water due to it burt at $30^{o} C$ .

07. The p-BLOCK ELEMENTS (XII)

189583 $V - A$ group precipitate was dissolved in $H N O_{3}$ and treated with excess of $N H_{4} O H$ . It gives a white ppt. because of

1

C u (O H)_{2}

2

C d (O H)_{2}

3

B i (O H)_{3}

4

H g (O H)_{2}

Explanation:

(c) When the black ppt. of $B i_{2} S_{3}$ is dissolved in $50 %$ $H N O_{3}$ and a solution of $N H_{4} O H$ is added. A white ppt. of $B i (O H)_{3}$ is obtained.