The S-Block Elements

Q1 FREE PREVIEW

PYQ

The correct order of density is

[JEE Main 2022, 25 Jul (Shift 2)]

a

\(Be > Mg > Ca > Sr\)

b

\(Sr > Ca > Mg > Be\)

c

\(Sr > Be > Mg > Ca\)

d

\(Be > Sr > Mg > Ca\)

✓ Correct answer: c)

\(Sr > Be > Mg > Ca\)

Explanation

\(\begin{aligned}&\begin{array}{cc}\text { Element } & \text { Density }\left( g m / c m ^3\right) \\Be & 1.84 \\Mg & 1.74 \\Ca & 1.55 \\Sr & 2.63\end{array}\\&Ca \text { has least density among the given elements. }\end{aligned}\)

Q2 FREE PREVIEW

PYQ

Determine the type of oxide formed by an elements (A) which has smallest size among following:

Li, Na, K, Be, B, Mg

Memory Based Question 29/Jan/25 Evening shift

a

\({\mathrm{A}}_{2}{\mathrm{O}}_{3}\)

b

AO

c

\({\mathrm{AO}}_{2}\)

d

\({\mathrm{A}}_{2}{\mathrm{O}}_{2}\)

✓ Correct answer: a)

\({\mathrm{A}}_{2}{\mathrm{O}}_{3}\)

Explanation

The element with the smallest size among Li, Na, K, Be, B, Mg is Boron (B).

Boron forms B₂O₃ which corresponds to the A₂O₃ type of oxide.

Correct answer: Option A

Q3 FREE PREVIEW

PYQ

The correct order of melting points of the following salts is:
LiCl (I)
LiF (II)
LiBr (III)

a

I > II > III

b

II > I > III

c

III > II > I

d

II > III > I

✓ Correct answer: b)

II > I > III

Explanation

Smaller the size of anion, smaller is the covalent character and higher will be its melting point. Hence, the order of melting point of lithium salts is LiF > LiCl > LiBr.

Q4 FREE PREVIEW

PYQ

Identify the correct order of standard enthalpy of formation of sodium halides

[JEE Main 2023, 13 Apr (Shift 2)]

a

\(NaI < NaBr < NaCl < NaF\)

b

\(NaF < NaCl < NaBr < NaI\)

c

\(NaCl < NaF < NaBr < NaI\)

d

\(NaI < NaBr < NaF < NaCl\)

✓ Correct answer: a)

\(NaI < NaBr < NaCl < NaF\)

Explanation

For a given metal \(\Delta_{ f } H ^0\) always becomes less negative from fluoride to iodide. Therefore correct order of standard enthalpy of formation of \(NaX\) is \(Na I < NaBr\) \(< NaCl < NaF\)

Q5 FREE PREVIEW

PYQ

Identify the correct statements about alkali metals

(A) The order of standard reduction potential \(\left( M ^{+} \mid M \right)\) for alkali metal ions is \(Na > Rb > Li\).
(B) LiI is highly soluble in water.
(C) Lithium carbonate is highly stable to heat.
(D) Potassium dissolved in concentrated liquid ammonia is blue in colour and paramagnetic.
(E) All the alkali metal hydrides are ionic solids.

Choose the correct answer from the options given below

[JEE Main 2023, 24 Jan (Shift 2)]

a

(A), (B) and (D) only

b

(C) and (E) only

c

(A) and (E) only

d

(A), (B) and (E) only

✓ Correct answer: d)

(A), (B) and (E) only

Explanation

\(Na > Cs > Li -\) true \(\{\) If considered with sign \(\}\)

CsI is less soluble in water due to smaller hydration enthalpy of it's two ions
\(Li _2 CO _3\) is not so stable to heat and gets converted into \(Li _2 O\) and \(CO _2\).
Potassium dissolved in liquid ammonia give deep blue solutions that are paramagnetic but in the concentrated solution, the blue. All the alkali metal hydrides are ionic solid (True).

Q6

PYQ

The correct order of melting points of the following salts is:
LiCl (I)
LiF (II)
LiBr (III)

a

I > II > III

b

II > I > III

c

III > II > I

d

II > III > I

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Q7

PYQ

Determine the type of oxide formed by an elements (A) which has smallest size among following:

Li, Na, K, Be, B, Mg

Memory Based Question 29/Jan/25 Evening shift

a

\({\mathrm{A}}_{2}{\mathrm{O}}_{3}\)

b

AO

c

\({\mathrm{AO}}_{2}\)

d

\({\mathrm{A}}_{2}{\mathrm{O}}_{2}\)

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Q8

PYQ

Better method for preparation of \(BeF _2\), among the following is

[JEE Main 2023, 13 Apr (Shift 2)]

a

\(\left( NH _4\right)_2 BeF _4 \xrightarrow{\Delta} BeF _2\)

b

\(BeH _2+ F _2 \xrightarrow{\Delta} BeF _2\)

c

\(Be + F _2 \xrightarrow{\Delta} BeF _2\)

d

\(BeO + C + F _2 \xrightarrow{\Delta} BeF _2\)

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Q9

PYQ

The number of water molecules in gypsum, dead burnt plaster and plaster of Paris, respectively are

[JEE Main 2021, 27 Aug (Shift 1)]

a

2,0 and 1

b

\( 0.5,0 \) and 2

c

5,0 and \( 0.5 \)

d

2,0 and \( 0.5 \)

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Q10

PYQ

The major component/ingredient of Portland Cement is:

[JEE Main 2021, 31 Aug (Shift 1)]

a

tricalcium silicate

b

dicalcium aluminate

c

dicalcium silicate

d

tricalcium aluminate

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Q11

PYQ

Given below are two statements : One is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A): Sodium is about 30 times as abundant as potassium in the oceans.

Reason (R): Potassium is bigger in size than sodium.

In the light of above statements, choose the correct answer from the options given below

[JEE Main 2023, 8 Apr (Shift 2)]

a

Both (A) and (R) are true and (R) is the correct explanation of (A)

b

(A) is true but (R) is false.

c

(A) is false but (R) is true.

d

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

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Q12

PYQ

What are the products formed in sequence when excess of \(CO _2\) is passed in slaked lime?

[JEE Main 2021, 26 Aug (Shift 1)]

a

\(Ca \left( HCO _3\right)_2, CaCO _3\)

b

\(CaO , CaCO _3\)

c

\(CaCO _3, Ca \left( HCO _3\right)_2\)

d

\(CaO , Ca \left( HCO _3\right)_2\)

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Q13

PYQ

Structure of \(BeCl _2\) in solid state, vapour phase and at very high temperature respectively are

[JEE Main 2023, 6 Apr (Shift 2)]

a

Dimeric, Polymeric, Monomeric

b

Polymeric, Dimeric, Monomeric

c

Monomeric, Dimeric, Polymeric

d

Polymeric, Monomeric, Dimeric

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Q14

PYQ

The metal mainly used in devising photoelectric cells is:

[JEE Main 2020, 2 Sep (Shift 1)]

a

\(Rb\)

b

\(Cs\)

c

\(Li\)

d

\(Na\)

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Q15

PYQ

Two elements A and B have similar chemical properties. They don't form
solid hydrogencarbonates, but react with nitrogen to form nitrides. A
and B, respectively, are :

a

Na and Rb

b

Na and Ca

c

Cs and Ba

d

Li and Mg

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Q16

PYQ

Match List - I with List - II.
List - I List - II

(A) Sodium Carbonate (I) Deacon
(B) Titanium (II) Castner-Kellner
(C) Chlorine (III) van-Arkel
(D) Sodium hydroxide (IV) Solvay

Choose the correct answer from the options given below:

[JEE Main 2021, 26 Feb (Shift 2)]

a

(A)-(IV), (B)-(III), (C)-(I), (D)-(II)

b

(A)-(III), (B)-(II), (C)-(I), (D)-(IV)

c

(A)-(I), (B)-(III), (C)-(IV), (D)-(II)

d

(A)-(IV), (B)-(I), (C)-(II), (D)-(III)

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Q17

PYQ

Match List- I with List-II:
List- I List-II

(A) NaOH (I) Acidic

(B) \(Be ( OH )_2\) (II) Basic

(C) \(Ca ( OH )_2\) (III) Amphoteric
(D) \(B ( OH )_3\)
(E) \(Al ( OH )_3\)

Choose the most appropriate answer from the options given below:

[JEE Main 2021, 27 Jul (Shift 1)]

a

(A)-(II), (B)-(I), (C)-(II), (D)-(III), (E)-(III)

b

(A)-(II), (B)-(III), (C)-(II), (D)-(I), (E)-(III)

c

(A)-(II), (B)-(II), (C)-(III), (D)-(II), (E)-(III)

d

(A)-(II), (B)-(II), (C)-(III), (D)-(I), (E)-(III)

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Q18

PYQ

Choose the correct statement(s):
(A) Beryllium oxide is purely acidic in nature.
(B) Beryllium carbonate is kept in the atmosphere of \(CO _2\).
(C) Beryllium sulphate is readily soluble in water.
(D) Beryllium shows anomalous behavior.

Choose the correct answer from the options given below:

a

(A), (B) and (C) only

b

(B), (C) and (D) only

c

(A) and (B) only

d

(A) only

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Q19

PYQ

Number of paramagnetic oxides among the following given oxides is
\(Li _2 O , CaO , Na _2 O _2, KO _2, MgO\) and \(K _2 O\)

[JEE Main 2021, 1 Sep (Shift 2)]

a

0

b

1

c

2

d

3

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Q20

PYQ

Which of the following will precipitate first when aqueous solution containing sulphate ions are added?

a

\({\mathrm{Mg}}^{+2}\)

b

\(C{a}^{+2}\)

c

\(S{r}^{+2}\)

d

\(B{a}^{+2}\)

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Q21

PYQ

Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R):

Assertion (A): \(BeCl _2\) and \(MgCl _2\) produce characteristic flame.
Reason (R): The excitation energy is high in \(BeCl _2\) and \(MgCl _2\).
In the light of the above statements, choose the correct answer from the option given below :

[JEE Main 2023, 15 Apr (Shift 1)]

a

Both (A) and (R) are true but (R) is NOT the correct explanation of \(( A )\)

b

(A) is false but (R) is true

c

Both (A) and (R) are true and (R) is the correct explanation of (A)

d

(A) is true but ( \(R )\) is false.

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Q22

PYQ

What is the purpose of adding gypsum to cement?

[JEE Main 2023, 8 Apr (Shift 1)]

a

To facilitate the hydration of cement

b

To speed up the process of setting

c

To slow down the process of setting

d

To give a hard mass

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Q23

PYQ

One of the by-products formed during the recovery of \(NH _3\) from solvay process is: \(\quad\)

[JEE Main 2021, 17 Mar (Shift 2)]

a

\(NaHCO _3\)

b

\(CaCl _2\)

c

\(Ca ( OH )_2\)

d

\(NH _4 Cl\)

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Q24

PYQ

Assertion (A): During the boiling of water having temporary hardness, \(\mathrm{Mg}\left(\mathrm{HCO}_{3}\right)_{2}\) is converted to \(\mathrm{MgCO}_{3}\).

Reason (R): The solubility product of \(\mathrm{Mg}(\mathrm{HCO_{3}})_{2}\) is greater than that of \(\mathrm{MgCO}_{3}\).

In the light of the above statements, choose the most appropriate answer from the options given below:

[JEE Main 2021, 18 Mar (Shift 1)]

a

Both (A) and (R) are true and (R) is the correct explanation of \((\mathrm{A})\)

b

(A) is false but (R) is true

c

(A) is true but (R) is false

d

Both (A) and (R) are true but (R) is NOT the correct explanation of \((\mathrm{A})\)

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Q25

PYQ

Match List-I with List-II:

List-I	List-II
(A) Ca(OCl)Cl	(I) Antacid
(B) \(CaSO _4 \cdot \frac{1}{2} H _2 O\)	(II) Cement
(C) \(CaO\)	(III) Bleach
(D) \(CaCO _3\)	(IV) Plaster of Paris

Choose the most appropriate answer from the options given below:

[JEE Main 2021, 18 Mar (Shift 1)]

a

(A)-(III), (B)-(II), (C)-(IV), (D)-(I)

b

(A)-(III), (B)-(II), (C)-(I), (D)-(IV)

c

(A)-(III), (B)-(IV), (C)-(II), (D)-(I)

d

(A)-(I), (B)-(IV), (C)-(III), (D)-(II)

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Q26

PYQ

Alkali metal from the following with least melting point is:

[JEE Main 2023, 11 Apr (Shift 2)]

a

\(Rb\)

b

\(K\)

c

\(Na\)

d

\(Cs\)

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Q27

PYQ

Given below are two statements, one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A): Beryllium has less negative value of reduction potential compared to the other alkaline earth metals.
Reason (R): Beryllium has large hydration energy due to small size of \(Be ^{2+}\) but relatively large value of atomization enthalpy.
In the light of the above statements, choose the most appropriate answer from the options given below.

[JEE Main 2023, 24 Jan (Shift 2)]

a

\(A\) is correct but \(R\) is not correct

b

Both \(A\) and \(R\) are correct and \(R\) is the correct explanation of \(A\).

c

\(A\) is not correct but \(R\) is correct

d

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

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Q28

PYQ

The compound which does not exist is

[JEE Main 2023, 10 Apr (Shift 1)]

a

\({\mathrm{NaO}}_{2}\)

b

\(\left( NH _4\right)_2 BeF _4\)

c

\(BeH _2\)

d

\(PbEt _4\)

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Q29

PYQ

The density of alkali metals is in the order

[JEE Main 2023, 12 Apr (Shift 1)]

a

\(Na < K < Cs < Rb\)

b

\(K < Na < Rb < Cs\)

c

\(K < Cs < Na < Rb\)

d

\(Na < Rb < K < Cs\)

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Q30

PYQ

\(Be ( OH )_2\) react with \(Sr ( OH )_2\) to yield an ionic salt. Choose the incorrect option related to this reaction from the following:

a

Be is tetrahedrally coordinated in the ionic salt.

b

The reaction is an example of acid - base neutralization reaction.

c

Both \(Sr\) and Be elements are present in the ionic salt.

d

The elements Be is present in the cationic part of the ionic salt.

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Q31

PYQ

\(Be ( OH )_2\) react with \(Sr ( OH )_2\) to yield an ionic salt. Choose the incorrect option related to this reaction from the following:

[JEE Main 2023, 13 Apr (Shift 1)]

a

Be is tetrahedrally coordinated in the ionic salt.

b

The reaction is an example of acid - base neutralization reaction.

c

Both \(Sr\) and Be elements are present in the ionic salt.

d

The elements Be is present in the cationic part of the ionic salt.

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Q32

PYQ

Given below are two statements:
Statement-I: Lithium and Magnesium do not form superoxide
Statement-II: The ionic radius of \(Li ^{+}\)is larger than ionic radius of \(Mg ^{2+}\)
In the light of the above statements, choose the most appropriate answer from the options given below:

[JEE Main 2023, 8 Apr (Shift 1)]

a

Statement-I is incorrect but Statement-II is correct

b

Statement-I is correct but Statement-II is incorrect

c

Both Statement-I and Statement-II are correct

d

Both Statement-I and Statement-II are incorrect

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Q33

PYQ

Match List-I with List-II.

List-I (Industry)	List-II (Waste Generated)
(A) Steel plants	(I) Gypsum
(B) Thermal power plants	(II) Fly ash
(C) Fertilizer industries	(III) Slag
(D) Paper mils	(IV) Bio-degradable Wastes

Choose the correct answer from the options given below:

[JEE Main 2023, 10 Apr (Shift 1)]

a

(A)-(III), (B)-(II), (C)-(I), (D)-(IV)

b

(A)-(II), (B)-(III), (C)-(IV), (D)-(I)

c

(A)-(IV), (B)-(I), (C)-(II), (D)-(III)

d

(A)-(III), (B)-(IV), (C)-(I), (D)-(II)

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Q34

PYQ

Among the statements a - d, the correct ones are :

(a) Lithium has the highest hydration enthalpy among the alkali metals.

(b) Lithium chloride is insoluble in pyridine.

(c) Lithium cannot form ethynide upon its reaction with ethyne.

(d) Both lithium and magnesium react slowly with \( \mathrm{H}_{2} \mathrm{O} \).

a

(a), (b) and (d) only

b

(b) and (c) only

c

(a) and (d) only

d

(a), (c) and (d) only

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Q35

PYQ

The setting time of Cement is increased by adding

a

Clay

b

Silica

c

Limestone

d

Gypsum

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Q36

PYQ

When gypsum is heated to \(393 K\), it forms:

[JEE Main 2020, 8 Jan (Shift 1)]

a

\(CaSO _4 \cdot 0.5 H _2 O\)

b

Dead burnt plaster

c

Anhydrous \(CaSO _4\)

d

\(CaSO _4 \cdot 5 H _2 O\)

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Q37

PYQ

The conversion of hydroxyapatite occurs due to presence of \(F ^{-}\)ions in water. The correct formula of hydroxyapatite is:

[JEE Main 2021, 26 Aug (Shift 1)]

a

\(\left[ Ca _3\left( PO _4\right)_2 \cdot CaF _2\right]\)

b

\(\left[3 Ca _3\left( PO _4\right)_2 \cdot Ca ( OH )_2\right]\)

c

\(\left[3 Ca _3\left( PO _4\right)_2 \cdot CaF _2\right]\)

d

\(\left[3 Ca ( OH )_2 \cdot CaF _2\right]\)

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Q38

PYQ

Number of water molecules in washing soda and soda ash respectively are

[JEE Main 2023, 10 Apr (Shift 2)]

a

10 and 1

b

1 and 10

c

1 and 0

d

10 and 0

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Q39

PYQ

Lime reacts exothermally with water to give 'A' which has low solubility in water. Aqueous solution of ' \(A\) ' is often used for the test of \(CO _2\), a test in which insoluble B is formed. If \(B\) is further reacted with \(CO _2\) then soluble compound is formed. 'A' is

[JEE Main 2023, 10 Apr (Shift 1)]

a

Quick lime

b

Slaked lime

c

Lime water

d

White lime

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Q40

PYQ

The alkaline earth metal sulphate(s) which are readily soluble in water is/are:
(I) BeSO₄

(II) MgSO₄

(III) CaSO₄

Choose the correct answer from the options given below:

a

(I) only

b

(II) only

c

(I) and (II)

d

(II) and (III)

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Q41

PYQ

Match List-I with List-II:

List-I	List-II
(A) \(\mathrm{Be}\)	(I) Treatment of cancer
(B) \(\mathrm{Mg}\)	(II) Extraction of metals
(C) \(\mathrm{Ca}\)	(III) Incendiary bombs and Windows of X-ray tubes
(D) \(\mathrm{Ra}\)	(IV) Bearings for motor & engines

Choose the most appropriate answer from the option given below:

[JEE Main 2021, 18 Mar (Shift 2)]

a

(A)-(III); (B)-(IV); (C)-(V); (D)-(II)

b

(A)-(IV); (B)-(III); (C)-(I); (D)-(II)

c

(A)-(III); (B)-(IV); (C)-(II); (D)-(I)

d

(A)-(IV); (B)-(III); (C)-(II); (D)-(I)

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Q42

PYQ

Lithium nitrate and sodium nitrate, when heated separately, respectively, give:

[JEE Main 2022, 29 Jul (Shift 1)]

a

\(LiNO _2\) and \(NaNO _2\)

b

\(Li _2 O\) and \(Na _2 O\)

c

\(Li _2 O\) and \(NaNO _2\)

d

\(LiNO _2\) and \(Na _2 O\)

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Q43

PYQ

Assertion (A): Gypsum is used for making fireproof wall boards.
Reason (R): Gypsum is unstable at high temperatures.
In the light of the above statements, choose the correct answer from the options given below

[JEE Main 2023, 1 Feb (Shift 2)]

a

Both (A) and (R) are correct but (R) is not the correct explanation of \(( A )\).

b

(A) is correct but ( \(R )\) is not correct.

c

(A) is not correct but (R) is correct.

d

Both (A) and (R) are correct and (R) is the correct explanation of (A).

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Q44

PYQ

Identify the correct statements about alkali metals

(A) The order of standard reduction potential \(\left( M ^{+} \mid M \right)\) for alkali metal ions is \(Na > Rb > Li\).
(B) CsI is highly soluble in water.
(C) Lithium carbonate is highly stable to heat.
(D) Potassium dissolved in concentrated liquid ammonia is blue in colour and paramagnetic.
(E) All the alkali metal hydrides are ionic solids.

Choose the correct answer from the options given below

a

(A), (B) and (D) only

b

(C) and (E) only

c

(A) and (E) only

d

(A), (B) and (E) only

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Q45

PYQ

Match List-I with List-II:
List-I List-II
(A) \(K\) (I) Thermonuclear reactions
(B) \(KCl\) (II) Fertilizer
(C) \(KOH\) (III) Sodium potassium pump
(D) \(Li\) (IV) Absorbent of \(CO _2\)

Choose the correct answer from the options given below:

[JEE Main 2023, 11 Apr (Shift 1)]

a

(A)-(III), (B)-(II), (C)-(IV), (D)-(I)

b

(A)-(IV), (B)-(I), (C)-(III), (D)-(II)

c

(A)-(IV), (B)-(III), (C)-(I), (D)-(II)

d

(A)-(III), (B)-(IV), (C)-(II), (D)-(I)

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Q46

PYQ

The conversion of hydroxyapatite occurs due to presence of \({\mathrm{F}}^{-}\)ions in water. The correct formula of hydroxyapatite is:

a

\( \left[3 \mathrm{Ca}_{3}\left(\mathrm{PO}_{4}\right)_{2} \cdot \mathrm{Ca}(\mathrm{OH})_{2}\right] \)

b

\( \left[3 \mathrm{Ca}(\mathrm{OH})_{2} \cdot \mathrm{CaF}_{2}\right] \)

c

\( \left[\mathrm{Ca}_{3}\left(\mathrm{PO}_{4}\right)_{2} \cdot \mathrm{CaF}_{2}\right] \)

d

\( \left[3 \mathrm{Ca}_{3}\left(\mathrm{PO}_{4}\right)_{2} \cdot \mathrm{CaF}_{2}\right] \)

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Q47

PYQ

When gypsum is heated to \(393 K\), it forms:

a

\(CaSO _4 \cdot 0.5 H _2 O\)

b

Dead burnt plaster

c

Anhydrous \(CaSO _4\)

d

\(CaSO _4 \cdot 5 H _2 O\)

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Q48

PYQ

Match List-I with List-II:
List-I List-II
(A) \(K\) (I) Thermonuclear reactions
(B) \(KCl\) (II) Fertilizer
(C) \(KOH\) (III) Sodium potassium pump
(D) \(Li\) (IV) Absorbent of \(CO _2\)

Choose the correct answer from the options given below:

a

(A)-(III), (B)-(II), (C)-(IV), (D)-(I)

b

(A)-(IV), (B)-(I), (C)-(III), (D)-(II)

c

(A)-(IV), (B)-(III), (C)-(I), (D)-(II)

d

(A)-(III), (B)-(IV), (C)-(II), (D)-(I)

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Q49

PYQ

Choose the correct statement from the following :

[JEE Main 2021, 27 Aug (Shift 2)]

a

The standard enthalpy of formation for alkali metal bromides becomes less negative on
descending the group.

b

LiF has least negative standard enthalpy of formation among alkali metal fluorides.

c

The low solubility of CsI in water is due to its high lattice enthalpy.

d

Among the alkali metal halides, LiF is least soluble in water.

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Q50

PYQ

A s-block element (M) reacts with oxygen to form an oxide of the formula \(M{O}_{2}\). The oxide is pale yellow in colour and paramagnetic. The element ( M ) is:

[JEE Main 2021, 20 Jul (Shift 1)]

a

Na

b

K

c

Mg

d

Ca

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