s-Block Elements

NEET (UG) 2023MCQEasy📈 Topic in 25% papers+4−1

Ques. 1NEET (UG) 2023

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the correct answer from the options given below :

Both A and R are true but R is NOT the correct explanation of A.
A is true but R is false
A is false but R is true
Both A and R are true and R is the correct explanation of A.

Answer

(2) A is true but R is false

Solution

Alkali metals dissolve in liquid ammonia giving ammoniated cations and ammoniated electrons:

M+(x+y)NH3 [M(NH3)x]+ + [e(NH3)y]-

The deep blue colour is due to the ammoniated electron, which absorbs in the visible region; the unpaired ammoniated electrons make the solution paramagnetic. So A is true.

The blue colour is not due to amide; on standing, the solution slowly liberates H2 and forms amide, NaNH2 (colourless). So R is false.

Answer: (2)

Out of syllabus

Keep practising — s-Block Elements

Ques. 2NEET (UG) 2023

Which one of the following statements is correct?

All enzymes that utilise ATP in phosphate transfer require Ca as the cofactor.
The bone in human body is an inert and unchanging substance.
Mg plays roles in neuromuscular function and interneuronal transmission.
The daily requirement of Mg and Ca in the human body is estimated to be 0.2-0.3 g.

Out of syllabus

Ques. 3NEET (UG) 2022

Identify the incorrect statement from the following

Alkali metals react with water to form their hydroxides.
The oxidation number of K in KO2 is +4.
Ionisation enthalpy of alkali metals decreases from top to bottom in the group.
Lithium is the strongest reducing agent among the alkali metals.

Out of syllabus

Ques. 4NEET (UG) 2022

Match List - I with List - II Choose the correct answer from the options given below :

(a)-(iv), (b)-(i), (c)-(iii), (d)-(ii)
(a)-(iii), (b)-(iv), (c)-(ii), (d)-(i)
(a)-(i), (b)-(iii), (c)-(iv), (d)-(ii)
(a)-(ii), (b)-(iii), (c)-(i), (d)-(iv)

Out of syllabus

Ques. 5NEET (UG) 2022 (Phase 2)

CaCl2 and Ca(OCl)2 are components of

Lime water
Gypsum
Portland cement
Bleaching powder

Out of syllabus

Ques. 6NEET (UG) 2021

Among the following alkaline earth metal halides, one which is covalent and soluble in organic solvents is :

Beryllium chloride
Calcium chloride
Strontium chloride
Magnesium chloride

Out of syllabus

Ques. 7NEET (UG) 2021

The structures of beryllium chloride in solid state and vapour phase, are :

Chain in both
Chain and dimer, respectively
Linear in both
Dimer and Linear, respectively

Out of syllabus

Ques. 8NEET (UG) 2020

The following metal ion activates many enzymes, participates in the oxidation of glucose to produce ATP and with Na+, is responsible for the transmission of nerve signals.