WB JEE 2021 | Some s Block Elements Question 5 | Chemistry

WB JEE 2021

MCQ (Single Correct Answer)

-0.25

Indicate the products (X) and (Y) in the following reactions

Na₂S + nS(n = 1 $$-$$ 8) $$\to$$ (X)

Na₂SO₃ + S $$\to$$ (Y)

(X)	(Y)
$$N{a_2}{S_2}{O_3}$$	$$N{a_2}{S_2}$$

(X)	(Y)
$$N{a_2}{S_{(n + 1)}}$$	$$N{a_2}{S_2}{O_3}$$

(X)	(Y)
$$N{a_2}{S_n}$$	$$N{a_2}{S_2}{O_3}$$

(X)	(Y)
$$N{a_2}{S_5}$$	$$N{a_2}{S_2}{O_4}$$

WB JEE 2021

MCQ (Single Correct Answer)

-0.25

The white precipitate (Y), obtained on passing colorless and odourless gas (X) through an ammoniacal solution of NaCl, losses about 37% of its weight on heating and a white residue (Z) of basic nature is left. Identify (X), (Y) and (Z) from following sets.

(X)	(Y)	(Z)
$${N_2}$$	$${(N{H_4})_2}C{O_3}$$	$$N{H_4}Cl$$

(X)	(Y)	(Z)
$${O_2}$$	$$NaN{H_4}C{O_3}$$	$$NaHC{O_3}$$

(X)	(Y)	(Z)
$$C{O_2}$$	$$N{H_4}HC{O_3}$$	$${(N{H_4})_2}C{O_3}$$

(X)	(Y)	(Z)
$$C{O_2}$$	$$NaHC{O_3}$$	$$N{a_2}C{O_3}$$

WB JEE 2020

MCQ (Single Correct Answer)

-0.25

In the extraction of Ca by electro reduction of molten CaCl₂ some CaF₂ is added to the electrolyte for the following reason :

To keep the electrolyte in liquid state at temperature lower than the m.p. of CaCl₂

To effect precipitation of Ca

To effect the electrolysis at lower voltage

To increase the current efficiency

WB JEE 2019

MCQ (Single Correct Answer)

-0.33

The compound, which evolves carbon dioxide on treatment with aqueous solution of sodium bicarbonate at 25$$^\circ$$C, is

C₆H₅OH

CH₃COCl

CH₃CONH₂

CH₃COOC₂H₅

PREVIOUS NEXT

WB JEE Subjects

Chemistry

Physical Chemistry

Some Basic Concepts of Chemistry Atomic Structure Redox Reaction Gaseous State Chemical Equilibrium Liquid Solution Ionic Equilibrium Thermodynamics Chemical Kinetics Radioactivity and Nuclear Chemistry Electrochemistry Solid State Surface Chemistry

Inorganic Chemistry

Periodic Table Chemical Bonding Metallurgy Hydrogen and It's Compounds Some s Block Elements Some P Block Elements d and f Block Elements Coordination Compounds

Organic Chemistry

IUPAC Nomenclatures General Organic Chemistry Isomerism Hydrocarbons Halogen Derivatives Alcohol and Ether Aldehyde and Ketone Aromatic Chemistry Carbonyl Compounds Carboxylic Acids and Amines Polymers Biomolecules Practical Chemistry Chemistry In Everyday Life

Mathematics

Algebra

Logarithms Sequence and Series Quadratic Equations Complex Numbers Permutations and Combinations Mathematical Induction and Binomial Theorem Matrices and Determinants Vector Algebra Three Dimensional Geometry Probability Statistics Sets and Relations

Trigonometry

Properties of Triangle Inverse Trigonometric Functions Trigonometric Functions & Equations

Coordinate Geometry

Straight Lines and Pair of Straight Lines Circle Parabola Ellipse and Hyperbola

Calculus

Functions Limits, Continuity and Differentiability Differentiation Application of Derivatives Indefinite Integrals Definite Integration Application of Integration Differential Equations