13 th group elements (p-block) practice · Medium

A compound $(A)$ of boron reacts with $\mathrm{NMe}_3$ to give an adduct $(B)$ which on hydrolysis gives a compound $(C)$ and hydrogen gas. Compound $(C)$ is an acid. The adduct $(B)$ is

In Hall-Heroult process, the following is used for reducing $\mathrm{Al}_{2} \mathrm{O}_{3}$ :-

The element which exists in liquid state for a wide range of temperature and can be used for measuring high temperature is

Assertion (A) : Aluminium trimethyl is a dimer having structure like that of ${AlCl}_3$.

Reason (R) : There is three-centre two-electron bonding in ${Al}-{C}-{Al}$ bridge.

The precious stone aquamarine is:

Consider the following reaction

${H_3}B{O_3}\xrightarrow{\Delta }A\xrightarrow[\Delta ]{{{\text{Red}}\,\,{\text{hot}}}}B$

$A$ and $B$ respectively are

Consider the following statement about the following reactions :

$A$ : $2 {H}_2 {O}({l})+2 {~F}_2({~g}) \rightarrow 4 {HF}({g})+{O}_2({~g})$

$B$ : ${BF}_3+{HF} \rightarrow {HBF}_4$

I. Reaction ($A$) is redox reaction whereas reaction $(B)$ is acid-base reaction

II. In reaction ($A$) ${H}_2 {O}$ is oxidising agent.

III. In reaction $({B}), {BF}_3$ is Lewis base.

Choose the correct statement(s) :

Amorphous boron on burning in air forms:

In the reaction ${\mathrm{B}_2}{\mathrm{O}_3} + \mathrm{C} + \mathrm{C}{\mathrm{l}_2} \to A + \mathrm{CO}.$ The A is

Which of the following is not correct in case of boron nitride?

Diborane cannot be obtained from

The incorrect statement reading ‘x’ in the reaction is $B{F_3} + LiAl{H_4}\xrightarrow{{\mathrm{Ether}}}\left( x \right) + LiF + Al{F_3}$

${13^{th}}$ group element with least melting point is:

Standard electrode potential values, $E^{{S}}$ for ${Al}^{3+} / {Al}$ is $-1.66 \mathrm{~V}$ and that of ${Tl}^{3+} / {Tl}$ is $+1.26 \mathrm{~V}$. Which of the following is incorrect regarding the given information?

Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R:

Assertion A : The stability order of +1 oxidation state of $\mathrm{Ga}$, $\mathrm{In}$ and $\mathrm{Tl}$ is $\mathrm{Ga} < \mathrm{In} < \mathrm{Tl}$.

Reason R : The inert pair effect stabilizes the lower oxidation state down the group.

In the light of the above statements, choose the correct answer from the options given below :

Boric acid is an acid because its molecule

In borax bead test which compound is formed?

Anodised aluminium is:

In which of the following compound '3C-2e' bonds are present:

Boric acid is not used:

When Al is added to KOH solution

${Na}_2 {B}_4 {O}_7 \cdot 10 {H}_2 {O}$ is correctly represented by

Orthoboric acid when heated to red hot, gives :

Which one of the following has the highest Lewis acid strength?

Which of the following pair have almost the same atomic radii

Select a correct statement about boric acid

Diborane is prepared on large scale by

Assertion (A) : $\mathrm{B}(\mathrm{OH})_3$ is a good lubricant and slippery.

Reason (R) : $\mathrm{B}(\mathrm{OH})_3$ has a layer structure.

The correct statements among the following is;

(I) Boric acid is a weak monobasic lewis acid.

(II) Boron trioxide is acidic and reacts with basic (metallic) oxides forming metal borates.

(III) Oxides of indium and thallium are amphoteric.

The relative stability of +1 oxidation state of group 13 elements follows the order