Given below are two statements: Statement I : $${\mathrm{S}}_8$$ solid undergoes disproportionation reaction under alkaline conditions to form $${\mathrm{S}}^{2-}$$ and $${\mathrm{S}}_2{\mathrm{O}}_3{}^{2-}$$. Statement II : $${\mathrm{ClO}}_4^{-}$$ can undergo disproportionation reaction under acidic condition. In the light of the above statements, choose the most appropriate answer from the options given below :

Choose the correct statements from the following A. All group 16 elements form oxides of general formula $${\mathrm{EO}}_2$$ and $${\mathrm{EO}}_3$$, where $$\mathrm{E}=\mathrm{S},\mathrm{Se},\mathrm{Te}$$ and $$\mathrm{Po}$$. Both the types of oxides are acidic in nature. B. $${\mathrm{TeO}}_2$$ is an oxidising agent while $${\mathrm{SO}}_2$$ is reducing in nature. C. The reducing property decreases from $${\mathrm{H}}_2\mathrm{S}$$ to $${\mathrm{H}}_2$$ Te down the group. D. The ozone molecule contains five lone pairs of electrons. Choose the correct answer from the options given below:

Consider the oxides of group 14 elements $${\mathrm{SiO}}_2,{\mathrm{GeO}}_2,{\mathrm{SnO}}_2,{\mathrm{PbO}}_2,\mathrm{CO}$$ and $$\mathrm{GeO}$$. The amphoteric oxides are

The compound that is white in color is

Give below are two statements: Statement - I: Noble gases have very high boiling points. Statement - II: Noble gases are monoatomic gases. They are held together by strong dispersion forces. Because of this they are liquefied at very low temperature. Hence, they have very high boiling points. In the light of the above statements, choose the correct answer from the options given below:

Identify the incorrect pair from the following :

On passing a gas, '$$\mathrm{X}$$', through Nessler's regent, a brown precipitate is obtained. The gas '$$\mathrm{X}$$' is

A and B formed in the following reactions are: $$\begin{array}{rl}& {\mathrm{CrO}}_2{\mathrm{Cl}}_2+4\mathrm{NaOH}\to \mathrm{A}+2\mathrm{NaCl}+2{\mathrm{H}}_2\mathrm{O},\\ & \mathrm{A}+2\mathrm{HCl}+2{\mathrm{H}}_2{\mathrm{O}}_2\to \mathrm{B}+3{\mathrm{H}}_2\mathrm{O}\end{array}$$

Choose the correct statements about the hydrides of group 15 elements. A. The stability of the hydrides decreases in the order $${\mathrm{NH}}_3>{\mathrm{PH}}_3>{\mathrm{AsH}}_3>{\mathrm{SbH}}_3>{\mathrm{BiH}}_3$$. B. The reducing ability of the hydride increases in the order $${\mathrm{NH}}_{3}C.Amongthehydrides,$$\mathrm{NH}_3$$isstrongreducingagentwhile$$\mathrm{BiH}_3$$ismildreducingagent.D.Thebasicityofthehydridesincreasesintheorder$$\mathrm{NH}_3 Choose the most appropriate from the options given below :

Given below are two statements : Statement (I) : The gas liberated on warming a salt with dil $${\mathrm{H}}_2{\mathrm{SO}}_4$$, turns a piece of paper dipped in lead acetate into black, it is a confirmatory test for sulphide ion. Statement (II) : In statement-I the colour of paper turns black because of formation of lead sulphite. In the light of the above statements, choose the most appropriate answer from the options given below :

The Lassiagne's extract is boiled with dil $${\mathrm{HNO}}_3$$ before testing for halogens because,

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Both rhombic and monoclinic sulphur exist as $${\mathrm{S}}_8$$ while oxygen exists as $${\mathrm{O}}_2$$. Reason (R) : Oxygen forms $$p\pi -p\pi$$ multiple bonds with itself and other elements having small size and high electronegativity like $$\mathrm{C},\mathrm{N}$$, which is not possible for sulphur. In the light of the above statements, choose the most appropriate answer from the options given below :

On reaction of Lead Sulphide with dilute nitric acid which of the following is not formed?

Identify the correct statements about p-block elements and their compounds. (A) Non metals have higher electronegativity than metals. (B) Non metals have lower ionisation enthalpy than metals. (C) Compounds formed between highly reactive nonmetals and highly reactive metals are generally ionic. (D) The non-metal oxides are generally basic in nature. (E) The metal oxides are generally acidic or neutral in nature. Choose the correct answer from the options given below :

Identify the incorrect statements about group 15 elements : (A) Dinitrogen is a diatomic gas which acts like an inert gas at room temperature. (B) The common oxidation states of these elements are $$-3,+3$$ and +5. (C) Nitrogen has unique ability to form $$\mathrm{p}\pi -\mathrm{p}\pi$$ multiple bonds. (D) The stability of +5 oxidation states increases down the group. (E) Nitrogen shows a maximum covalency of 6. Choose the correct answer from the options given below :

In qualitative test for identification of presence of phosphorous, the compound is heated with an oxidising agent. Which is further treated with nitric acid and ammonium molybdate respectively. The yellow coloured precipitate obtained is :

Give 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 $$\mathrm{Ga}$$, In and $$\mathrm{Tl}$$ is Ga 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:

Among the following halogens $${\mathrm{F}}_2,{\mathrm{Cl}}_2,{\mathrm{Br}}_2\text{ and }{\mathrm{I}}_2$$ Which can undergo disproportionation reactions?

The number of neutrons present in the more abundant isotope of boron is '$$x$$'. Amorphous boron upon heating with air forms a product, in which the oxidation state of boron is '$$y$$'. The value of $$x+y$$ is _________ .

The correct statements from the following are : (A) The decreasing order of atomic radii of group 13 elements is $$\mathrm{Tl}>\mathrm{In}>\mathrm{Ga}>\mathrm{Al}>\mathrm{B}$$. (B) Down the group 13 electronegativity decreases from top to bottom. (C) $$\mathrm{Al}$$ dissolves in dil. $$\mathrm{HCl}$$ and liberates $${\mathrm{H}}_2$$ but conc. $${\mathrm{HNO}}_3$$ renders $$\mathrm{Al}$$ passive by forming a protective oxide layer on the surface. (D) All elements of group 13 exhibits highly stable +1 oxidation state. (E) Hybridisation of $$\mathrm{Al}$$ in $$[\mathrm{Al}({\mathrm{H}}_2\mathrm{O}{)}_6{]}^{3+}$$ ion is $${\mathrm{sp}}^3{\mathrm{d}}^2$$. Choose the correct answer from the options given below :