Some s Block Elements · Chemistry · WB JEE
MCQ (Single Correct Answer)
1
Na$$_2$$CO$$_3$$ is prepared by Solvay process but K$$_2$$CO$$_3$$ cannot be prepared by the same because
WB JEE 2023
2
A sample of MgCO3 is dissolved in dil. HCl and the solution is neutralized with ammonia and buffered with NH4Cl / NH4OH. Disodium hydrogen phosphate reagent is added to the resulting solution. A white precipitate is formed. What is the formula of the precipitate?
WB JEE 2022
3
To a solution of colourless sodium salt, a solution of lead nitrate was added to have a white precipitate which dissolves in warm water and reprecipitates on cooling. Which of the following acid radical is present in the salt?
WB JEE 2022
4
Indicate the products (X) and (Y) in the following reactions
Na2S + nS(n = 1 $$-$$ 8) $$\to$$ (X)
Na2SO3 + S $$\to$$ (Y)
Na2S + nS(n = 1 $$-$$ 8) $$\to$$ (X)
Na2SO3 + S $$\to$$ (Y)
WB JEE 2021
5
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.
WB JEE 2021
6
In the extraction of Ca by electro reduction of molten CaCl2 some CaF2 is added to the electrolyte for the following reason :
WB JEE 2020
7
The compound, which evolves carbon dioxide on treatment with aqueous solution of sodium bicarbonate at 25$$^\circ$$C, is
WB JEE 2019
8
The reactive species in chlorine bleach is
WB JEE 2019
9
Which of the following is least thermally stable?
WB JEE 2018
10
Which of the following solutions will turn violet when a drop of lime juice is added to it?
WB JEE 2017