P-block elements practice · Mixed difficulty

Swimming pools are disinfected by bubbling through water with a controlled quantity of:

$\left[{Fe}\left({H}_2 {O}\right)_5 {NO}\right]^{2+}$ is a complex formed during the brown ring test for ${NO}_3^{-}$ion. In this complex.

Assertion (A): Sulphur shows paramagnetism.

Reason (R): In vapour state sulphur partly exists as $\mathrm{S}_2$ molecule which has two unpaired electrons in the antibonding $\hat{\pi}$-orbitals.

Statement-I: Red phosphorus glows in dark and is frequently used in glow signs.

Statement-II: White phosphorus is an allotropic form of red phosphorus.

Assertion (A) Elementary phosphorus exists in three principal allotropic forms, i.e. white (or yellow), red (or violet) and black.

Reason (R) Of the three forms, white phosphorus is the most important and most reactive.

The last member of inert gas family is:

Assertion (A): Most of the reactions of fluorine are exothermic.

Reason (R): Fluorine forms small and strong bond with it and other elements.

Ammonia is dried over

Which of the following is called Berthelot’s salt?

Statement I: The dipole moment of $\mathrm{NF}_3$ is less than $\mathrm{NH}_3$

Statement II: The presence of lone pair of electrons on nitrogen atom shows an additive contribution in dipole moment of $\mathrm{NH}_3$ whereas it shows negative contribution towards dipole moment of $\mathrm{NF}_3$

Phosphorus pentoxide cannot be used to dry:

Assertion (A): $\mathrm{N}_2$ is more stable than $\mathrm{N}_2^{+}$.
Reason (R): Bond order of $\mathrm{N}_2$ is 2.5 while $\mathrm{N}_2^+$ is 3.

Which substance chars when warmed with conc. ${H_2}S{O_4}$ ?

Collectively the elements of group 15 are called -

What is the oxidising agent chlorine water?

Presence of sulphide ion cannot be confirmed by:

Noble gases are group of elements which exhibit very

Iodine exists in which form in iodised salt

Hydrolysis of ${PCl}_5$ gives:

In a reaction, 4 mole of electrons are transferred to 1 mole of ${HNO}_3$, the possible product obtained due to reduction is :-

The stability of +2 oxidation state among Si, Ge, Sn and Pb increase in the sequence

Which is bad conductor of electricity?

In Kipp’s apparatus, ${\mathrm{H}_2}\mathrm{S}$ is prepared:

Noble gases are used in discharge tubes to gives different colours. Reddish orange glow is due to

The noble gas used in the preparation of first noble gas compound was:

Poison for platinum, a catalyst in contact process of ${H_2}S{O_4}$ is:

Compound of Sulphur used in electrical transformer is:

Polyanion formation is maximum in

Statement I: All the halogens exhibit -1 oxidation state.

Statement II: The oxidation states of +4 and +6 occur in the oxides and oxoacids of chlorine and bromine.

Hot conc. ${H_2}S{O_4}$ act as moderately strong oxidizing agent. It oxidises both metals and non-metals. Which of the following element is oxidized by conc. ${H_2}S{O_4}$ into two gaseous products.