p-Block Elements · JEE Main previous year questions

When $81.0\mathrm{g}$ of aluminium is allowed to react with $128.0\mathrm{g}$ of oxygen gas, the mass of aluminium oxide produced in grams is ____ . (Nearest integer) Given : Molar mass of $\mathrm{Al}$ is $27.0\mathrm{g}\mathrm{mo}{\mathrm{l}}^{-1}$ Molar mass of $\mathrm{O}$ is $16.0\mathrm{g}\mathrm{mo}{\mathrm{l}}^{-1}$

The number of molecules/ions that show linear geometry among the following is _________. ${\mathrm{SO}}_2,{\mathrm{BeCl}}_2,{\mathrm{CO}}_2,{\mathrm{N}}_3^{-},{\mathrm{NO}}_2,{\mathrm{F}}_2\mathrm{O},{\mathrm{XeF}}_2,{\mathrm{NO}}_2^{+},{\mathrm{I}}_3^{-},{\mathrm{O}}_3$

In Carius method for estimation of halogens, $180\text{ mg}$ of an organic compound produced $143.5\text{ mg}$ of $\mathrm{AgCl}$ . The percentage composition of chlorine in the compound is _________ %. (Given : molar mass in ${\text{g mol}}^{-1}$ of $\mathrm{Ag}:108,\mathrm{Cl}:35.5$ )

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 :

1. A.Both (A) and (R) are correct but (R) is not the correct explanation of (A)
2. B.(A) is correct but (R) is not correct
3. C.(A) is not correct but (R) is correct
4. D.Both (A) and (R) are correct and (R) is the correct explanation of (A)

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

1. A.Sulphur
2. B.Nitric oxide
3. C.Lead nitrate
4. D.Nitrous oxide

Number of oxygen atoms present in chemical formula of fuming sulphuric acid is ___________.

Thiosulphate reacts differently with iodine and bromine in the reactions given below: $2{\text{ S}}_2{\text{O}}_3^{2-}+{\text{I}}_2\to {\text{S}}_4{\text{O}}_6^{2-}+2{\text{I}}^{-}$ ${\text{S}}_2{\text{O}}_3^{2-}+5{\text{Br}}_2+5{\text{H}}_2\text{O}\to 2{\text{SO}}_4^{2-}+4{\text{Br}}^{-}+10{\text{H}}^{+}$ Which of the following statements justifies the above dual behaviour of thiosulphate?

1. A.Thiosulphate undergoes oxidation by bromine and reduction by iodine in these reactions
2. B.Bromine is a weaker oxidant than iodine
3. C.Bromine is a stronger oxidant than iodine
4. D.Bromine undergoes oxidation and iodine undergoes reduction in these reactions

Given below are two statements : Statement (I) : Kjeldahl method is applicable to estimate nitrogen in pyridine. Statement (II) : The nitrogen present in pyridine can easily be converted into ammonium sulphate in Kjeldahl method. In the light of the above statements, choose the correct answer from the options given below :

1. A.Both Statement I and Statement II are true
2. B.Both Statement I and Statement II are false
3. C.Statement I is true but Statement II is false
4. D.Statement I is false but Statement II is true

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 $p\pi -p\pi$ 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 :

1. A.(A), (C), (E) only
2. B.(D) and (E) only
3. C.(A), (B), (D) only
4. D.(B), (D), (E) only

Which of the following nitrogen containing compound does not give Lassaigne's test ?

1. A.Glycine
2. B.Phenyl hydrazine
3. C.Urea
4. D.Hydrazine

1. A.$\text{B}=\text{C}=\text{1-Propanol}$
2. B.$\text{B}=\text{1-Propanol }\text{C}=\text{2-Propanol}$
3. C.$\text{B}=\text{C}=\text{2-Propanol}$
4. D.$\text{B}=\text{2-Propanol }\text{C}=\text{1-Propanol}$

Vanillin compound obtained from vanilla beans, has total sum of oxygen atoms and $\pi$ electrons is _________.

Given below are two statements : Statement (I) : $\mathrm{Si}{\mathrm{O}}_2$ and $\mathrm{Ge}{\mathrm{O}}_2$ are acidic while $\mathrm{SnO}$ and $\mathrm{PbO}$ are amphoteric in nature. Statement (II) : Allotropic forms of carbon are due to property of catenation and $p\pi -d\pi$ bond formation. In the light of the above statements, choose the most appropriate answer from the options given below :

1. A.Statement I is false but Statement II is true
2. B.Both Statement I and Statement II are false
3. C.Both Statement I and Statement II are true
4. D.Statement I is true but Statement II is false

Following Kjeldahl's method, $1\text{ g}$ of organic compound released ammonia, that neutralised $10\text{ mL}$ of $2\mathrm{M}$ ${\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4$. The percentage of nitrogen in the compound is ________ $\%$.

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

1. A.A and B only
2. B.C and D only
3. C.A and D only
4. D.B and C only

Aluminium chloride in acidified aqueous solution forms an ion having geometry

1. A.Square planar
2. B.Octahedral
3. C.Trigonal bipyramidal
4. D.Tetrahedral

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

1. A.Silver halides are soluble in $\mathrm{HN}{\mathrm{O}}_3$.
2. B.$\mathrm{AgCN}$ is soluble in $\mathrm{HN}{\mathrm{O}}_3$.
3. C.$\mathrm{N}{\mathrm{a}}_2\mathrm{S}$ and $\mathrm{NaCN}$ are decomposed by $\mathrm{HN}{\mathrm{O}}_3$.
4. D.$\mathrm{A}{\mathrm{g}}_2\mathrm{S}$ is soluble in $\mathrm{HN}{\mathrm{O}}_3$.

The compound formed by the reaction of ethanal with semicarbazide contains _________ number of nitrogen atoms.

Number of compounds among the following which contain sulphur as heteroatom is ___________. Furan, Thiophene, Pyridine, Pyrrole, Cysteine, Tyrosine

Given below are two statements: Statement I : Fluorine has most negative electron gain enthalpy in its group. Statement II : Oxygen has least negative electron gain enthalpy in its group. In the light of the above statements, choose the most appropriate from the options given below

1. A.Both Statement I and Statement II are true
2. B.Both Statement I and Statement II are false
3. C.Statement I is false but Statement II is true
4. D.Statement I is true but Statement II is false

Anomalous behavior of oxygen is due to its

1. A.large size and low electronegativity
2. B.small size and high electronegativity
3. C.small size and low electronegativity
4. D.large size and high electronegativity

Given below are two statements : Statement (I) : In the Lanthanoids, the formation of ${\text{Ce}}^{+4}$ is favoured by its noble gas configuration. Statement (II) : ${\text{Ce}}^{+4}$ is a strong oxidant reverting to the common +3 state. In the light of the above statements, choose the most appropriate answer from the options given below :

1. A.Both Statement I and Statement II are false
2. B.Statement I is true but Statement II is false
3. C.Both Statement I and Statement II are true
4. D.Statement I is false but Statement II is true

The number of non-polar molecules from the following is _______. $\text{HF},{\text{H}}_2\text{O},{\text{SO}}_2,{\text{H}}_2,{\text{CO}}_2,{\text{CH}}_4,{\text{NH}}_3,\text{HCl},{\text{CHCl}}_3,{\text{BF}}_3$