NEET Chemistry The s-Block Elements Questions Solved

Which ion forms a hydroxide highly soluble in water?

(a) Ni²⁺

(b) K⁺

(d) Al³⁺

(b) Alkali metal hydroxides are highly soluble in water.

Difficulty Level:

(a)
8%
(b)
65%
(c)
8%
(d)
21%

What would you observe if excess of dilute NaOH solution is added and shaken with an aqueous solution of aluminium chloride?

(a) A permanent white precipitate is formed immediately

(b) No change at first but a white precipitate is formed on standing

(d) A green precipitate which turns red on standing in air

#Some Important Compounds of Na

(c)

${AlCl}_{3} + 3 NaOH \overset{}{\to} Al (OH)_{3} + 3 NaCl Al (OH)_{3} + 3 NaOH \overset{}{\to} {Na}_{3} {AlO}_{3} + 3 H_{2} O soluble$

Difficulty Level:

(a)
26%
(b)
24%
(c)
46%
(d)
6%

A colourless salt gives violet colour to Bunsen flame and also turns moistured litmus paper blue. It Is:

(a) Na₂CO₃

(b) KNO₃

(d) Cu(OH)₂

#Physical Properties & Characteristics

Difficulty Level:

(a)
18%
(b)
33%
(c)
37%
(d)
14%

Strongest reducing agent among the following is:

(a) K

(b) Na

(d) Mg

#Physical Properties & Characteristics

(a) Alkali metals are strongest reducing agents. Also, their reducing power increases down the group.

Difficulty Level:

(a)
48%
(b)
32%
(c)
11%
(d)
11%

When crystal of caustic soda is exposed to air, a liquid layer is deposited because:

(a) crystal melts

(b) crystal loses water

(d) crystal sublimes

#Physical Properties & Characteristics

$2 NaOH + {CO}_{2} \underset{}{\to} {Na}_{2} {CO}_{3} + H_{2} O$ 2

Difficulty Level:

(a)
4%
(b)
15%
(c)
76%
(d)
7%

Which one of the following is formed on dissolving I₂ in aqueous solution of KI ?

(a) KIO₄

(b) KIO

(d) KIO₃

#Physical Properties & Characteristics

Difficulty Level:

(a)
16%
(b)
13%
(c)
34%
(d)
39%

Which of the following statements is correct for CsBr₃?

(a) it is a covalent compound

(b) It contains Cs²⁺ and Br^- ions

(d) It contains Cs⁺ and ${Br}_{3}^{-}$ ions

#Chemical Properties

(d) ${CsBr}_{3} \overset{}{\to} {Cs}^{+} + {Br}_{3}^{-}$

Difficulty Level:

(a)
16%
(b)
13%
(c)
37%
(d)
36%

Hypo is chemically:

(a) Na₂S₂O₃.2H₂O

(b) Na₂S₂O₃.3H₂O

(d) Na₂S₂O₃.5H₂O

#Some Important Compounds of Na

(d) It is chemical formula of Hypo.

Difficulty Level:

(a)
37%
(b)
18%
(c)
18%
(d)
28%

If NaOH is added to an aqueous solution of Zn²⁺ ions, a white precipitate appears and on adding axcess NaOH, the precepitate dissolves. In this solution zinc exists in the:

(a) cationic part

(b) anionic part

(d) there is no zinc left in the solution

#Some Important Compounds of Na

(b)

${Zn}^{2 +} + 2 NaOH \overset{}{\to} 2 {Na}^{+} + Zn (OH)_{2} Zn (OH)_{2} + 2 NaOH \overset{}{\to} {Na}_{2} {ZnO}_{2} + 2 H_{2} O Thus, {Na}_{2} {ZnO}_{2} forms 2 {Na}^{+} and {[{ZnO}_{2}]}^{2 -} ions .$

Difficulty Level:

(a)
32%
(b)
35%
(c)
23%
(d)
12%

Brine is chemically:

(a) conc. solution of Na₂CO₃

(b) conc. solution of Na₂SO₄

(d) conc. solution of alum

#Physical Properties & Characteristics

Difficulty Level:

(a)
11%
(b)
13%
(c)
72%
(d)
6%