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11. THE P-BLOCK ELEMENTS

189997 Graphite is used as dry lubricant because of its

1 layer type structure

2

s p^{3}

hybridisation

3 presence of dangling bonds

4 presence of two types of bond lengths

11. THE P-BLOCK ELEMENTS

189998 Borax has the molecular formula

1

N a_{2} [B_{4} O_{3} (O H)_{4}] .6 H_{2} O

2

N a_{2} [B_{4} O_{5} (O H)_{4}] .6 H_{2} O

3

N a_{2} [B_{4} O_{5} (O H)_{4}] .8 H_{2} O

4

N a_{2} [B_{4} O_{6} (O H)_{2}] .8 H_{2} O

Explanation:

Borax, also called sodium tetraborate, is a powdery white mineral that has been used as a cleaning product for several decades.
Formula of borax is $N a_{2} [B_{4} O_{5} (O H)_{4}] \cdot 8 H_{2} O$ .

11. THE P-BLOCK ELEMENTS

189999 Compare $π -$ bond strength between $B$ and $N$ given in two compounds $(I)$ $\begin{matrix} {(C H_{3})}_{3} S i - N B H_{2} \\ | \\ S i {(C H_{3})}_{3} \end{matrix}$ $(I I)$ $\begin{matrix} {(C H_{3})}_{3} C - N B H_{2} \\ | \\ C {(C H_{3})}_{3} \end{matrix}$

1 There is no

π -

bond character between

B

and

N

2 Same in

I

and

I I

3

I > I I

4

I I > I

11. THE P-BLOCK ELEMENTS

190000 $(i) A l \overset{N_{2}}{\to} A$ $(i i) A l \overset{c}{\to} B$ Here $A$ and $B$ on hydrolysis respectively gives

1

N H_{3}, C_{2} H_{2}

2

N O, C H_{4}

3

N H_{3}, C H_{4}

4

N O, C_{2} H_{2}

Explanation:

$A = A l N \overset{H_{2} O}{\to} N H_{3}$
$B = A l_{4} C_{3} \overset{H_{2} O}{\to} C H_{4}$

11. THE P-BLOCK ELEMENTS

189997 Graphite is used as dry lubricant because of its

1 layer type structure

2

s p^{3}

hybridisation

3 presence of dangling bonds

4 presence of two types of bond lengths

11. THE P-BLOCK ELEMENTS

189998 Borax has the molecular formula

1

N a_{2} [B_{4} O_{3} (O H)_{4}] .6 H_{2} O

2

N a_{2} [B_{4} O_{5} (O H)_{4}] .6 H_{2} O

3

N a_{2} [B_{4} O_{5} (O H)_{4}] .8 H_{2} O

4

N a_{2} [B_{4} O_{6} (O H)_{2}] .8 H_{2} O

Explanation:

Borax, also called sodium tetraborate, is a powdery white mineral that has been used as a cleaning product for several decades.
Formula of borax is $N a_{2} [B_{4} O_{5} (O H)_{4}] \cdot 8 H_{2} O$ .

11. THE P-BLOCK ELEMENTS

189999 Compare $π -$ bond strength between $B$ and $N$ given in two compounds $(I)$ $\begin{matrix} {(C H_{3})}_{3} S i - N B H_{2} \\ | \\ S i {(C H_{3})}_{3} \end{matrix}$ $(I I)$ $\begin{matrix} {(C H_{3})}_{3} C - N B H_{2} \\ | \\ C {(C H_{3})}_{3} \end{matrix}$

1 There is no

π -

bond character between

B

and

N

2 Same in

I

and

I I

3

I > I I

4

I I > I

11. THE P-BLOCK ELEMENTS

190000 $(i) A l \overset{N_{2}}{\to} A$ $(i i) A l \overset{c}{\to} B$ Here $A$ and $B$ on hydrolysis respectively gives

1

N H_{3}, C_{2} H_{2}

2

N O, C H_{4}

3

N H_{3}, C H_{4}

4

N O, C_{2} H_{2}

Explanation:

$A = A l N \overset{H_{2} O}{\to} N H_{3}$
$B = A l_{4} C_{3} \overset{H_{2} O}{\to} C H_{4}$

11. THE P-BLOCK ELEMENTS

189997 Graphite is used as dry lubricant because of its

1 layer type structure

2

s p^{3}

hybridisation

3 presence of dangling bonds

4 presence of two types of bond lengths

11. THE P-BLOCK ELEMENTS

189998 Borax has the molecular formula

1

N a_{2} [B_{4} O_{3} (O H)_{4}] .6 H_{2} O

2

N a_{2} [B_{4} O_{5} (O H)_{4}] .6 H_{2} O

3

N a_{2} [B_{4} O_{5} (O H)_{4}] .8 H_{2} O

4

N a_{2} [B_{4} O_{6} (O H)_{2}] .8 H_{2} O

Explanation:

Borax, also called sodium tetraborate, is a powdery white mineral that has been used as a cleaning product for several decades.
Formula of borax is $N a_{2} [B_{4} O_{5} (O H)_{4}] \cdot 8 H_{2} O$ .

11. THE P-BLOCK ELEMENTS

189999 Compare $π -$ bond strength between $B$ and $N$ given in two compounds $(I)$ $\begin{matrix} {(C H_{3})}_{3} S i - N B H_{2} \\ | \\ S i {(C H_{3})}_{3} \end{matrix}$ $(I I)$ $\begin{matrix} {(C H_{3})}_{3} C - N B H_{2} \\ | \\ C {(C H_{3})}_{3} \end{matrix}$

1 There is no

π -

bond character between

B

and

N

2 Same in

I

and

I I

3

I > I I

4

I I > I

11. THE P-BLOCK ELEMENTS

190000 $(i) A l \overset{N_{2}}{\to} A$ $(i i) A l \overset{c}{\to} B$ Here $A$ and $B$ on hydrolysis respectively gives

1

N H_{3}, C_{2} H_{2}

2

N O, C H_{4}

3

N H_{3}, C H_{4}

4

N O, C_{2} H_{2}

Explanation:

$A = A l N \overset{H_{2} O}{\to} N H_{3}$
$B = A l_{4} C_{3} \overset{H_{2} O}{\to} C H_{4}$

11. THE P-BLOCK ELEMENTS

189997 Graphite is used as dry lubricant because of its

1 layer type structure

2

s p^{3}

hybridisation

3 presence of dangling bonds

4 presence of two types of bond lengths

11. THE P-BLOCK ELEMENTS

189998 Borax has the molecular formula

1

N a_{2} [B_{4} O_{3} (O H)_{4}] .6 H_{2} O

2

N a_{2} [B_{4} O_{5} (O H)_{4}] .6 H_{2} O

3

N a_{2} [B_{4} O_{5} (O H)_{4}] .8 H_{2} O

4

N a_{2} [B_{4} O_{6} (O H)_{2}] .8 H_{2} O

Explanation:

Borax, also called sodium tetraborate, is a powdery white mineral that has been used as a cleaning product for several decades.
Formula of borax is $N a_{2} [B_{4} O_{5} (O H)_{4}] \cdot 8 H_{2} O$ .

11. THE P-BLOCK ELEMENTS

189999 Compare $π -$ bond strength between $B$ and $N$ given in two compounds $(I)$ $\begin{matrix} {(C H_{3})}_{3} S i - N B H_{2} \\ | \\ S i {(C H_{3})}_{3} \end{matrix}$ $(I I)$ $\begin{matrix} {(C H_{3})}_{3} C - N B H_{2} \\ | \\ C {(C H_{3})}_{3} \end{matrix}$

1 There is no

π -

bond character between

B

and

N

2 Same in

I

and

I I

3

I > I I

4

I I > I

11. THE P-BLOCK ELEMENTS

190000 $(i) A l \overset{N_{2}}{\to} A$ $(i i) A l \overset{c}{\to} B$ Here $A$ and $B$ on hydrolysis respectively gives

1

N H_{3}, C_{2} H_{2}

2

N O, C H_{4}

3

N H_{3}, C H_{4}

4

N O, C_{2} H_{2}

Explanation:

$A = A l N \overset{H_{2} O}{\to} N H_{3}$
$B = A l_{4} C_{3} \overset{H_{2} O}{\to} C H_{4}$