JEE Chemistry S Block Elements MCQs Set A

Question: Group 2 elements are called alkaline earth metals why? Choose the correct reason(s).

(i) Hydroxides formed by group 2 elements are alkaline in nature.
(ii) Their metal oxides are found in the earth’s crust.
(iii) Their oxides are alkaline in nature
(iv) Group 2 elements react with alkalies.

• a) (i), (ii) and (iii)
• b) (i) and (ii)
• c) (ii) and (iv)
• d) (ii) and (iii)

Answer: (i), (ii) and (iii)

Question: Which of the following alkali metal is highly radioactive?

• a) Francium
• b) Rubidium
• c) Caesium
• d) None of these

Answer: Francium

Question: Which of the following are found in biological fluids Na⁺, Mg²⁺, Ca²⁺, K⁺, Sr²⁺, Li⁺ and Ba²⁺

• a) Na⁺, K⁺, Mg²⁺and Ca²⁺
• b) Sr⁺, Li and Ba²⁺
• c) Na^{2 +}and K⁺
• d) None of these

Answer: Na⁺, K⁺, Mg²⁺and Ca²⁺

Question: Which of the following statements is not correct for alkali metals?

• a) Alkali metals exist in free state in nature
• b) Alkali metals are the most electropositive metals
• c) These metals have the largest size in a particular period of the periodic table
• d) None pf these

Answer: Alkali metals exist in free state in nature

Question: Which of the following has largest size ?

• a) Na^–
• b) Na
• c) Na⁺
• d) Can’t be predicted

Answer: Na^–

Question: Ionization potential of Na would be numerically the same as

• a) electron affinity of Na⁺
• b) electronegativity of Na⁺
• c) electron affinity of He
• d) ionization potential of Mg

Answer: electron affinity of Na⁺

Question: Which one of the following properties of alkali metals increases in magnitude as the atomic number rises ?

• a) Ionic radius
• b) Electronegativity
• c) Melting point
• d) First ionization energy.

Answer: Ionic radius

Question: Which of the following has density greater than water?

• a) Rb
• b) Na
• c) K
• d) None of these

Answer: Rb

Question: The elements of group 1 provide a colour to the flame of Bunsen burner due to

• a) low ionization potential
• b) low melting point
• c) softness
• d) presence of one electron in the outermost orbit

Answer: low ionization potential

Question: The metal that produces red-violet colour in the nonluminous flame is

• a) Rb
• b) Ba
• c) Ag
• d) Pb

Answer: Rb

Question: The alkali metals have low melting point. Which of the following alkali metal is expected to melt if the room temperature rises to 30°C?

• a) Cs
• b) K
• c) Na
• d) Rb

Answer: Cs

Question: In the case of the alkali metals

• a) the cation is smaller than the atom
• b) the cation is less stable than the atom
• c) the cation and the atom have about the same size
• d) the cation is larger than the atom

Answer: the cation is smaller than the atom

Question: The element which on burning in air gives peroxide is

• a) sodium
• b) caesium
• c) lithium
• d) rubidium

Answer: sodium

Question: Which one of the alkali metals, forms only, the normal oxide, M₂O on heating in air ?

• a) Li
• b) Rb
• c) K
• d) Na

Answer:  Li

Question: Which of the following is used as a source of oxygen in space capsules, submarines and breathing masks ?

• a) KO₂
• b) Li₂O
• c) Na₂O₂
• d) K₂O₂

Answer: KO₂

Question: The ionic mobility of alkali metal ions in aqueous solution is maximum for

• a) Rb⁺
• b) Na⁺
• c) Li⁺
• d) K⁺

Answer: Rb⁺

Question: For an aqueous solution under an electric field which of the following have lowest mobility ?

• a) Li⁺
• b) K⁺
• c) Na⁺
• d) Rb⁺

Answer: Li⁺

Question: Which of the following pairs of substances would give same gaseous product on reaction with water?

• a) Ca and CaH₂
• b) Ba and BaO₂
• c) Na and Na₂O₂
• d) Ca and CaO

Answer: Ca and CaH₂

Question: Which is the most basic of the following?

• a) Na₂O
• b) As₂O₃
• c) BaO
• d) Al₂O₃

Answer: Na₂O

Question: Which hydride is most stable

• a) LiH
• b) KH
• c) NaH
• d) CsH

Answer: LiH

Question: The most stable compound is

• a) LiF
• b) LiCl
• c) LiBr
• d) LiI

Answer: LiF

Question: Which of the following represents a correct sequence of reducing power of the following elements?

• a) Li > Cs > Rb
• b) Cs > Li > Rb
• c) Rb > Cs > Li
• d) Li > Rb > Cs

Answer: Li > Cs > Rb

Question:  What is the colour of solution of alkali metals in liquid ammonia?

• a) Blue
• b) Violet
• c) Bronze
• d) Green

Answer: Blue

Question: The alkali metals dissolve in liquid ammonia giving deep blue solution. The solution is __x__. In concentrated solution, the blue colour changes to __y___ and becomes __z__

• a) x = paramagnetic y = bronze z = diamagnetic
• b) x = paramagnetic y = black z = diamagnetic
• c) x = diamagnetic y = colourless z = paramagnetic
• d) x = paramagnetic y = colourless z = diamagnetic

Answer: x = paramagnetic y = bronze z = diamagnetic

Question: Na metal is stored in

• a) kerosene
• b) toluene
• c) C₆H₆
• d) alcohol

Answer: kerosene

Question: Which of the following metal is used along with lithium to make the alloy named ‘white metal’

• a) Lead
• b) Aluminium
• c) Nickel
• d) Silver

Answer: Lead

Question: Which of the following metal is used as a coolant in breeder nuclear reactors?

• a) Sodium
• b) Rubidium
• c) Potassium
• d) Caesium

Answer: Sodium

Question: Which is most basic in character ?

• a) CsOH
• b) NaOH
• c) KOH
• d) LiOH

Answer: CsOH

Question: Which compound will show the highest lattice energy ?

• a) NaF
• b) RbF
• c) CsF
• d) KF

Answer: NaF

Question: In crystals which one of the following ionic compounds would you expect maximum distance between centres of cations and anions?

• a) CsI
• b) LiF
• c) CsF
• d) LiI

Answer: CsI

Question: Among LiI, NaI, KI, the one which is more ionic and more soluble in water is

• a) KI
• b) LiI
• c) NaI
• d) None of these

Answer: KI

Question: On heating anhydrous Na₂CO₃, _____ is evolved

• a) no gas
• b) water vapour
• c) CO₂
• d) CO

Answer: no gas

Question: Which of the following does not illustrate the anomalous properties of lithium?

• a) Li is much softer than the other group I metals
• b) Li forms a nitride Li₃N unlike group I metals
• c) The ion of Li and its compounds are more heavily hydrated than those of the rest of the group
• d) The melting point and boiling point of Li are comparatively high

Answer: Li is much softer than the other group I metals

Question: Identify the correct statement

• a) Elemental sodium is easily oxidised
• b) Elemental sodium is insoluble in ammonia
• c) Elemental sodium is a strong oxidising agent
• d) Elemental sodium can be prepared and isolated by electrolysing an aqueous solution of sodium chloride

Answer: Elemental sodium is easily oxidised

Question: Washing soda has formula

• a) Na₂CO₃.10H₂O
• b) Na₂CO₃
• c) Na₂CO₃.3H₂O
• d) None of these

Answer: Na₂CO₃.10H₂O

Question: The process associated with sodium carbonate manufacture is known as

• a) LeBlanc
• b) Chamber
• c) Haber
• d) Castner

Answer: LeBlanc

Question: In Solvay ammonia process, sodium bicarbonate is precipitate due to

• a) reaction with brine solution
• b) reaction with NaOH
• c) reaction with CO₂
• d) presence of NH₃

Answer: reaction with brine solution

Question: Sodium carbonate is manufactured by Solvay process. The products which can be recycled are

• a) CO₂ and NH₃
• b) NaCl and CaO
• c) CO₂ and NH₄Cl
• d) CaCl₂ and CaO.

Answer: CO₂ and NH₃

Question: How NH₃ is recovered in Solvay process?

• a) By reaction of NH₄Cl and Ca(OH)₂
• b) By reaction of NH₄HCO₃ and NaCl
• c) By reaction of (NH₄)₂CO₃ with H₂O
• d) None of these

Answer: By reaction of NH₄Cl and Ca(OH)₂

Question: Why Solvay process cannot be extended to the manufacture of potassium carbonate?

• a) Potassium hydrogen carbonate is too soluble to be precipitated by the addition of ammonium hydrogencarbonate to a saturated solution of potassium chloride.
• b) Ammonium hydrogen carbonate does not react with potassium chloride
• c) Ammonium carbonate is precipitated out instead of potassium hydrogen carbonate on reaction of ammonium hydrogen carbonate with potassium chloride
• d) None of the above

Answer: Potassium hydrogen carbonate is too soluble to be precipitated by the addition of ammonium hydrogencarbonate to a saturated solution of potassium chloride.

Question:  Which of the following is/are present as impurity in crude sodium chloride, obtained by crystallisation of brine solution?

(i) Sodium sulphate        (ii) Calcium chloride
(iii) Magnesium chloride (iv) Potassium chloride

• a) (i), (ii) and (iii)
• b) (ii) and (iii)
• c) (i), (ii) and (iv)
• d) iv) (b) (ii) and (iii)

Answer: (i), (ii) and (iii)

Question: Which is manufactured by electrolysis of fused NaCl ?

• a) Na
• b) NaClO₃.
• c) NaOH
• d) NaClO

Answer: Na

Question: Baking soda is

• a) NaHCO₃
• b) Na₂CO₃
• c) K₂CO₃
• d) NaOH

Answer: NaHCO₃

Question: Baking powder contains

• a) NaHCO₃, Ca(H₂PO₂)₂ and starch
• b) NaHCO₃, Ca(H₂PO₂)₂
• c) NaHCO₃, starch
• d) NaHCO₃

Answer:  NaHCO₃, Ca(H₂PO₂)₂ and starch

Question: Which of the following is the most abundant ion within cell fluids?

• a) Potassium ions
• b) None of these
• c) Sodium ions
• d) Calcium ions

Answer: Potassium ions

Question: Which of the following is non-metallic?

• a) B
• b) Mg
• c) Be
• d) Al

Answer: B

Question:  Electronic configuration of calcium atom may be written as

• a) [Ar], 4s²
• b) [Ar], 4p²
• c) [Ne], 4p²
• d) [Ne], 4s²

Answer: [Ar], 4s²

Question: The outer electronic configuration of alkaline earth metal is

• a) ns²
• b) np⁶
• c) ns¹
• d) nd¹⁰

Answer: ns²

Question: Which of the following atoms will have the smallest size ?

• a) Be
• b) Mg
• c) Na
• d) Li

Answer: Be

Question: The first ionization energy of magnesium is lower than the first ionization energy of

• a) Beryllium
• b) Sodium
• c) Lithium
• d) Calcium

Answer: Beryllium

Question: The first ionization energies of alkaline earth metals are higher than those of alkali metals. This is because

• a) there is increase in the nuclear charge of alkaline earth metals
• b) there is decrease in the nuclear charge of alkaline earth metals
• c) there is no change in the nuclear charge
• d) none of these

Answer: there is increase in the nuclear charge of alkaline earth metals

Question: The most electropositive amongst the alkaline earth metals is

• a) barium
• b) magnesium
• c) beryllium
• d) calcium

Answer: barium

Question: Alkaline earth metals are not found free in nature because of

• a) their greater chemical reactivity
• b) their high boiling points
• c) their low melting points
• d) their thermal instability

Answer:  their greater chemical reactivity

Question: A firework gives out crimson coloured light. It contains a salt of

• a) Sr
• b) Ca
• c) Na
• d) Ba

Answer: Sr