Chemistry

This is a Assertion and Reason Type Questions as classified in NCERT Exemplar

(A)

In aluminium silicate, silicon is doped with group 13 elements and as aluminium is trivalent and silicon is tetravalent so, on replacing aluminium by Silicon, a negatively charged structure will be obtained. Both the statements assertion and reason are correct and reason is the correct explanation of assertion.

This is a Matching Type Questions as classified in NCERT Exemplar

(i)→ (b), (ii) → (c), (iii) → (b), (iv) → (a) (v)→ (b) (vi)→ (c)

This is a Matching Type Questions as classified in NCERT Exemplar

(i)→ (c) (ii)→ (d) (iii)→ (a) (iv)→ (e) (v)→ (b)

This is a Matching Type Questions as classified in NCERT Exemplar

(i)- (e), (ii)- (c), (iii)- (d), (iv)- (a) & (b)

This is a Multiple Choice Questions as classified in NCERT Exemplar

(B) & (D)

The following is the resonance structure of CO₂.

This is a Multiple Choice Questions as classified in NCERT Exemplar

(A), (B) & (D)

Two hydrogens forming bridge in B₂H₆ are peculiar in bonding and can be termed as 3 -centered-2-electron bond or banana bond. 1 s orbital  of each hydrogen overlaps with the hybrid orbital of one of the boron then delocalising the 2e−over three atoms making 3 -centered-2-electron bond.

This is a Multiple Choice Questions as classified in NCERT Exemplar

(B) & (C)

(B) Fullerene is an allotrope of carbon consisting of 60 carbon atoms bonded together through single and double bonds in such a manner that they form a hollow sphere like shape or a cage-like structure.

(C) In graphite, each carbon atom has one free/ delocalised electron that causes strong attraction between carbon atoms providing more stability to the overall structure of graphite

This is a Multiple Choice Questions as classified in NCERT Exemplar

(A) & (B)

Me₃SiCl is a soleuless liquid and is stable in anhydrous condition. When added in the process of polymerization, it blocks the end terminal of the silicone polymer and determines its chain length.

This is a Multiple Choice Questions as classified in NCERT Exemplar

(B) & (C)

Hybridisation of any atom in a molecule corresponds to the number or σ bonds it is making covalently with other atoms.

In CO₂, carbon is attached to two oxygen atoms through double bonds. Out of which two are σ bonds and the rest two are π bonds forming I−p π bonding between carbon and oxygen.

The two σ bonds correspond to the hybridization sp and give a linear shape to CO_2.

This is a Multiple Choice Questions as classified in NCERT Exemplar

(A) & (B)

The atomic radii decrease as one moves down the group from Al to Ga due to the shielding effect of electrons. As a result of this ineffective effect, the effective nuclear charge rises.