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11. THE P-BLOCK ELEMENTS

190032 A neutral molecule $X F_{3}$ has a zero dipole moment. The element $X$ is most likely

1 chlorine

2 boron

3 nitrogen

4 carbon

Explanation:

$B F_{3}$ has planar and symmetrical structure thus as a result the resultant of two bond moments, being equal and opposite to the third, cancels out and hence molecule possess zero dipole moment. 845-s134

11. THE P-BLOCK ELEMENTS

190037 Assertion : Stannous chloride gives grey precipitate with mercuric chloride, but stannic chloride does not do so.Reason : Stannous chloride is a powerful oxidising agent which oxidises mercuric chloride to metallic mercury.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

$S n^{4 +}$ is more stable than $S n^{2 +}$
So, $S n^{2 +}$ is oxidised to $S n^{4 +}$ by losing $2$ electrons when it reacts with mercuric chloride, i.e., $S n C l_{2}$ is a reducing agent.
$2 H g C l_{2} + S n C l_{2} \to H g_{2} C l_{2} + S n C l_{4}$
$H g_{2} C l_{2} + S n C l_{2} \to \underset{(g r e y p p t)}{2 H g} + S n C l_{4}$

11. THE P-BLOCK ELEMENTS

190038 Assertion : Diamond is a bad conductor.Reason : Graphite is a good conductor.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

11. THE P-BLOCK ELEMENTS

190039 Assertion : $P b I_{4}$ is a stable compound.Reason : Iodide stabilizes higher oxidation state

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

As we move down the group $I V A$ , $+ 2$ oxidation state becomes more stable. Thus $P b^{4 +}$ is not possible, i.e., $P b I_{4}$ is highly unstable. $I_{2}$ is a weak oxidising agent so it cannot oxidise $P b$ to $P b^{4 +}$ oxidation state. So assertion and reason both are wrong.

11. THE P-BLOCK ELEMENTS

190040 Assertion : $S i F_{6}^{2 -}$ is known but $S i C l_{6}^{2 -}$ is notReason : Size of fluorine is small and its lone pair of electrons interacts with $d -$ orbitals of $S i$ strongly.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

$S i F_{6}^{2 -}$ is known because $F$ has small size and thus the ion is quite stable unlike $S i C l_{6}^{2 -}$ in which size of $C l$ atom is large which destabilise it.

11. THE P-BLOCK ELEMENTS

190032 A neutral molecule $X F_{3}$ has a zero dipole moment. The element $X$ is most likely

1 chlorine

2 boron

3 nitrogen

4 carbon

Explanation:

$B F_{3}$ has planar and symmetrical structure thus as a result the resultant of two bond moments, being equal and opposite to the third, cancels out and hence molecule possess zero dipole moment. 845-s134

11. THE P-BLOCK ELEMENTS

190037 Assertion : Stannous chloride gives grey precipitate with mercuric chloride, but stannic chloride does not do so.Reason : Stannous chloride is a powerful oxidising agent which oxidises mercuric chloride to metallic mercury.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

$S n^{4 +}$ is more stable than $S n^{2 +}$
So, $S n^{2 +}$ is oxidised to $S n^{4 +}$ by losing $2$ electrons when it reacts with mercuric chloride, i.e., $S n C l_{2}$ is a reducing agent.
$2 H g C l_{2} + S n C l_{2} \to H g_{2} C l_{2} + S n C l_{4}$
$H g_{2} C l_{2} + S n C l_{2} \to \underset{(g r e y p p t)}{2 H g} + S n C l_{4}$

11. THE P-BLOCK ELEMENTS

190038 Assertion : Diamond is a bad conductor.Reason : Graphite is a good conductor.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

11. THE P-BLOCK ELEMENTS

190039 Assertion : $P b I_{4}$ is a stable compound.Reason : Iodide stabilizes higher oxidation state

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

As we move down the group $I V A$ , $+ 2$ oxidation state becomes more stable. Thus $P b^{4 +}$ is not possible, i.e., $P b I_{4}$ is highly unstable. $I_{2}$ is a weak oxidising agent so it cannot oxidise $P b$ to $P b^{4 +}$ oxidation state. So assertion and reason both are wrong.

11. THE P-BLOCK ELEMENTS

190040 Assertion : $S i F_{6}^{2 -}$ is known but $S i C l_{6}^{2 -}$ is notReason : Size of fluorine is small and its lone pair of electrons interacts with $d -$ orbitals of $S i$ strongly.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

$S i F_{6}^{2 -}$ is known because $F$ has small size and thus the ion is quite stable unlike $S i C l_{6}^{2 -}$ in which size of $C l$ atom is large which destabilise it.

11. THE P-BLOCK ELEMENTS

190032 A neutral molecule $X F_{3}$ has a zero dipole moment. The element $X$ is most likely

1 chlorine

2 boron

3 nitrogen

4 carbon

Explanation:

$B F_{3}$ has planar and symmetrical structure thus as a result the resultant of two bond moments, being equal and opposite to the third, cancels out and hence molecule possess zero dipole moment. 845-s134

11. THE P-BLOCK ELEMENTS

190037 Assertion : Stannous chloride gives grey precipitate with mercuric chloride, but stannic chloride does not do so.Reason : Stannous chloride is a powerful oxidising agent which oxidises mercuric chloride to metallic mercury.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

$S n^{4 +}$ is more stable than $S n^{2 +}$
So, $S n^{2 +}$ is oxidised to $S n^{4 +}$ by losing $2$ electrons when it reacts with mercuric chloride, i.e., $S n C l_{2}$ is a reducing agent.
$2 H g C l_{2} + S n C l_{2} \to H g_{2} C l_{2} + S n C l_{4}$
$H g_{2} C l_{2} + S n C l_{2} \to \underset{(g r e y p p t)}{2 H g} + S n C l_{4}$

11. THE P-BLOCK ELEMENTS

190038 Assertion : Diamond is a bad conductor.Reason : Graphite is a good conductor.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

11. THE P-BLOCK ELEMENTS

190039 Assertion : $P b I_{4}$ is a stable compound.Reason : Iodide stabilizes higher oxidation state

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

As we move down the group $I V A$ , $+ 2$ oxidation state becomes more stable. Thus $P b^{4 +}$ is not possible, i.e., $P b I_{4}$ is highly unstable. $I_{2}$ is a weak oxidising agent so it cannot oxidise $P b$ to $P b^{4 +}$ oxidation state. So assertion and reason both are wrong.

11. THE P-BLOCK ELEMENTS

190040 Assertion : $S i F_{6}^{2 -}$ is known but $S i C l_{6}^{2 -}$ is notReason : Size of fluorine is small and its lone pair of electrons interacts with $d -$ orbitals of $S i$ strongly.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

$S i F_{6}^{2 -}$ is known because $F$ has small size and thus the ion is quite stable unlike $S i C l_{6}^{2 -}$ in which size of $C l$ atom is large which destabilise it.

11. THE P-BLOCK ELEMENTS

190032 A neutral molecule $X F_{3}$ has a zero dipole moment. The element $X$ is most likely

1 chlorine

2 boron

3 nitrogen

4 carbon

Explanation:

$B F_{3}$ has planar and symmetrical structure thus as a result the resultant of two bond moments, being equal and opposite to the third, cancels out and hence molecule possess zero dipole moment. 845-s134

11. THE P-BLOCK ELEMENTS

190037 Assertion : Stannous chloride gives grey precipitate with mercuric chloride, but stannic chloride does not do so.Reason : Stannous chloride is a powerful oxidising agent which oxidises mercuric chloride to metallic mercury.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

$S n^{4 +}$ is more stable than $S n^{2 +}$
So, $S n^{2 +}$ is oxidised to $S n^{4 +}$ by losing $2$ electrons when it reacts with mercuric chloride, i.e., $S n C l_{2}$ is a reducing agent.
$2 H g C l_{2} + S n C l_{2} \to H g_{2} C l_{2} + S n C l_{4}$
$H g_{2} C l_{2} + S n C l_{2} \to \underset{(g r e y p p t)}{2 H g} + S n C l_{4}$

11. THE P-BLOCK ELEMENTS

190038 Assertion : Diamond is a bad conductor.Reason : Graphite is a good conductor.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

11. THE P-BLOCK ELEMENTS

190039 Assertion : $P b I_{4}$ is a stable compound.Reason : Iodide stabilizes higher oxidation state

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

As we move down the group $I V A$ , $+ 2$ oxidation state becomes more stable. Thus $P b^{4 +}$ is not possible, i.e., $P b I_{4}$ is highly unstable. $I_{2}$ is a weak oxidising agent so it cannot oxidise $P b$ to $P b^{4 +}$ oxidation state. So assertion and reason both are wrong.

11. THE P-BLOCK ELEMENTS

190040 Assertion : $S i F_{6}^{2 -}$ is known but $S i C l_{6}^{2 -}$ is notReason : Size of fluorine is small and its lone pair of electrons interacts with $d -$ orbitals of $S i$ strongly.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

$S i F_{6}^{2 -}$ is known because $F$ has small size and thus the ion is quite stable unlike $S i C l_{6}^{2 -}$ in which size of $C l$ atom is large which destabilise it.

11. THE P-BLOCK ELEMENTS

190032 A neutral molecule $X F_{3}$ has a zero dipole moment. The element $X$ is most likely

1 chlorine

2 boron

3 nitrogen

4 carbon

Explanation:

$B F_{3}$ has planar and symmetrical structure thus as a result the resultant of two bond moments, being equal and opposite to the third, cancels out and hence molecule possess zero dipole moment. 845-s134

11. THE P-BLOCK ELEMENTS

190037 Assertion : Stannous chloride gives grey precipitate with mercuric chloride, but stannic chloride does not do so.Reason : Stannous chloride is a powerful oxidising agent which oxidises mercuric chloride to metallic mercury.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

$S n^{4 +}$ is more stable than $S n^{2 +}$
So, $S n^{2 +}$ is oxidised to $S n^{4 +}$ by losing $2$ electrons when it reacts with mercuric chloride, i.e., $S n C l_{2}$ is a reducing agent.
$2 H g C l_{2} + S n C l_{2} \to H g_{2} C l_{2} + S n C l_{4}$
$H g_{2} C l_{2} + S n C l_{2} \to \underset{(g r e y p p t)}{2 H g} + S n C l_{4}$

11. THE P-BLOCK ELEMENTS

190038 Assertion : Diamond is a bad conductor.Reason : Graphite is a good conductor.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

11. THE P-BLOCK ELEMENTS

190039 Assertion : $P b I_{4}$ is a stable compound.Reason : Iodide stabilizes higher oxidation state

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

As we move down the group $I V A$ , $+ 2$ oxidation state becomes more stable. Thus $P b^{4 +}$ is not possible, i.e., $P b I_{4}$ is highly unstable. $I_{2}$ is a weak oxidising agent so it cannot oxidise $P b$ to $P b^{4 +}$ oxidation state. So assertion and reason both are wrong.

11. THE P-BLOCK ELEMENTS

190040 Assertion : $S i F_{6}^{2 -}$ is known but $S i C l_{6}^{2 -}$ is notReason : Size of fluorine is small and its lone pair of electrons interacts with $d -$ orbitals of $S i$ strongly.

1 If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

2 If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

3 If the Assertion is correct but Reason is incorrect.

4 If both the Assertion and Reason are incorrect.

Explanation:

$S i F_{6}^{2 -}$ is known because $F$ has small size and thus the ion is quite stable unlike $S i C l_{6}^{2 -}$ in which size of $C l$ atom is large which destabilise it.