The S Block Elements CBSE Questions & Answers

The S Block Elements

This is Chemistry Class 11 The s Block Elements CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
The general electronic configuration of \({\text{n}}{{\text{s}}^{\text{2}}}\)exists in:
  • A
    transition elements
  • B
    alkaline earth metals.
    Correct
  • C
    alkali metals.
  • D
    coordination compounds
2
The alkali metals and their salts impart characteristic colour to an oxidizing flame because:
  • A
    the smallest atomic size makes them to absorb radiation
  • B
    there is emission of radiation in the visible region from the excited electron
    Correct
  • C
    the largest atomic size makes them to emit radiation
  • D
    sufficient light energy is absorbed to make an atom gain an electron
3
Flame photometry is used to detect
  • A
    alkaline earth metals.
  • B
    alkali metals.
    Correct
  • C
    transition elements
  • D
    noble gases
4
The electronic configuration of \({\text{7}}{{\text{s}}^{\text{1}}}\) belongs to
  • A
    Lithium
  • B
    Francium
    Correct
  • C
    Rubidium
  • D
    Caesium
5
The alkali metals burn vigorously in oxygen forming oxides. Hence, potassium forms
  • A
    superoxide
    Correct
  • B
    hydroxide
  • C
    monoxide
  • D
    peroxide
6
What is the oxidation state of K in \({\text{K}}{{\text{O}}_{\text{2}}}?\)
  • A
    1.0
    Correct
  • B
    +4
  • C
    +2
  • D
    +3
7
\({\text{2M }} + {\text{ 2}}{{\text{H}}_{\text{2}}}{\text{O }} \to {\text{2}}{{\text{M}}^ + } + {\text{ 2O}}{{\text{H}}^ - } + {\text{ }}{{\text{H}}_{\text{2}}}\) What is M?
  • A
    alkaline earth metals.
  • B
    noble gases
  • C
    alkali metals.
    Correct
  • D
    transition elements
8
Lithium has most negative \({{\text{E}}^0}\) value,its reaction with water is less vigorous than that of sodium which has the least negative E0 value among the alkali metals. The reason is
  • A
    small size of sodium
  • B
    i is a proton donor
  • C
    low hydration energy
  • D
    high hydration energy
    Correct
9
When sodium is dissolved in liquid ammonia, a solution of deep blue colour is obtained. The colour of the solution is due to
  • A
    ammoniated sodium ion
  • B
    sodium amide
  • C
    sodium ion
  • D
    ammoniated electron
    Correct
10
The alkali metals dissolve in liquid ammonia giving deep blue solutions. When they become diamagnetic, the solution turns into
  • A
    purple colour
  • B
    green colour
  • C
    bronze colour
    Correct
  • D
    white colour
11
lithium halides are somewhat covalent because
  • A
    high polarisation capability of lithium ion
    Correct
  • B
    Li+ ion is very small in size and has low tendency to distort electron
  • C
    Li+ ion is very large in size and has high tendency to distort electron
  • D
    low polarisation capability of lithium ion
12
Choose the correct trend of the melting and boiling points in the alkali metal halides, MF, MCl, MI, MBr.
  • A
    MI <MF<MCl< MBr
  • B
    MCl > MBr > MI <MF
  • C
    MF > MCl > MBr > MI
    Correct
  • D
    MBr > MI <MF<MCl
13
All alkali metal halides are soluble in water except
  • A
    lithium
    Correct
  • B
    caesium
  • C
    Francium
  • D
    rubidium
14
Why is \({\text{K}}{{\text{O}}_{\text{2}}}\) paramagnetic ?
  • A
    because of one unpaired electron in \({\pi ^ * }\) 1p
  • B
    because of one unpaired electron in \({\pi ^ * }\) 2p
    Correct
  • C
    because of lattice energy effects
  • D
    because of increase in size of the metal ion
15
Alkali metal chlorides donot form hydrates except for one metal. Choose from among the options given below.
  • A
    Francium
  • B
    rubidium
  • C
    lithium
    Correct
  • D
    caesium