SSC CGL Chemistry Questions and Answers

Copper is second and gold is third. Option A (“Gold”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option B (“Copper”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option D (“Aluminium”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. The answer field, correct index and explanation therefore all identify Silver. Silver (Ag) has the highest electrical conductivity among all metals.

Option A (“2-butene”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option B (“1-butene”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option D (“But-1-ene”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. The answer field, correct index and explanation therefore all identify But-2-ene. CH3-CH=CH-CH3 is but-2-ene as the double bond starts at carbon 2 of a 4-carbon chain.

E cell = 1.1V. Option B (“Cu is oxidised to Cu²⁺ and Zn²⁺ is reduced to Zn”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option C (“Both zinc and copper are oxidised”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option D (“Both zinc and copper ions are reduced”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Identify the governing formula, definition or reaction and apply it consistently. The answer field, correct index and explanation therefore all identify Zn is oxidised to Zn²⁺ and Cu²⁺ is reduced to Cu. Daniell cell: Zn(s) oxidized at anode gives Zn2+; Cu2+ reduced at cathode gives Cu(s).

Moles = 36/18 = 2 moles.

H2SO4 to H+ + HSO4- and HSO4- to H+ + SO4^2-. Option A (“HCl”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option B (“H3PO4”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option D (“HNO3”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. The answer field, correct index and explanation therefore all identify H2SO4. H2SO4 is a dibasic (diprotic) acid with two ionizable H+ ions: H2SO4 to H+ + HSO4- and HSO4- to H+ + SO4^2-.

alyst in Contact process for SO3 formation from SO2 and O2. Option A (“Iron”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option B (“Platinum”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option D (“Nickel”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. The answer field, correct index and explanation therefore all identify Vanadium pentoxide. V2O5 (vanadium pentoxide) is used as catalyst in Contact process for SO3 formation from SO2 and O2.

ienophile (ethylene) undergoes cycloaddition to form cyclohexene. Option A (“Benzene + HNO3”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option C (“Propene + HBr”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option D (“Cyclohexane + Cl2”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Identify the governing formula, definition or reaction and apply it consistently. The answer field, correct index and explanation therefore all identify 1-3 butadiene + ethylene. Diels-Alder reaction: diene (1-3 butadiene) + dienophile (ethylene) undergoes cycloaddition to form cyclohexene.

catalyst) is an electrophilic addition reaction. Option A (“Elimination”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option C (“Substitution”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option D (“Rearrangement”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Identify the governing formula, definition or reaction and apply it consistently. The answer field, correct index and explanation therefore all identify Addition. Acid-catalyzed hydration of alkene (alkene + H2O with H2SO4 catalyst) is an electrophilic addition reaction.

In XeF6 Xe has 12 electrons (6 bond pairs). Option A (“8”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option B (“10”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option D (“14”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Identify the governing formula, definition or reaction and apply it consistently. The answer field, correct index and explanation therefore all identify 12.Xenon (Period 5) can expand its valence shell using 5d orbitals. In XeF6 Xe has 12 electrons (6 bond pairs).

H) and Br adds to middle carbon giving 2-bromopropane. Option A (“1-bromopropane”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option C (“1-bromopropene”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Option D (“3-bromopropane”) is incorrect because it does not satisfy the chemical formula, reaction, periodic trend, numerical relation, oxidation state or definition required by the question. Identify the governing formula, definition or reaction and apply it consistently. The answer field, correct index and explanation therefore all identify 2-bromopropane. By Markovnikov's rule H adds to terminal carbon (more H) and Br adds to middle carbon giving 2-bromopropane.