the s-block Elements Practice Questions - DPP for JEE

 Page 1


1. Alkali metals are generally extracted by
(a) reduction methods
(b) double decomposition methods
(c) displacement methods
(d) electrolytic methods
2. Which of the following represents a correct sequence of reducing power
of the following elements?
(a) Li > Cs > Rb
(b) Rb > Cs > Li
(c) Cs > Li > Rb
(d) Li > Rb > Cs
3. Strongest bond is in between
(a) CsF
(b) NaCl
(c) Both (a) and (b)
Page 2


1. Alkali metals are generally extracted by
(a) reduction methods
(b) double decomposition methods
(c) displacement methods
(d) electrolytic methods
2. Which of the following represents a correct sequence of reducing power
of the following elements?
(a) Li > Cs > Rb
(b) Rb > Cs > Li
(c) Cs > Li > Rb
(d) Li > Rb > Cs
3. Strongest bond is in between
(a) CsF
(b) NaCl
(c) Both (a) and (b)
IE
1
IE
2
(a) I 2372 5251
(b) II 520 7300
(c) III 900 1760
(d) IV 16803 380
(d) None of above
4. A metal salt solution forms a yellow precipitate with potassium
chromate in acetic acid, a white precipitate with dil H
2
SO
4
, but gives no
precipitate with NaCl. The metal salt solution will consist of
(a) PbCO
3
(b) BaCO
3
(c) MgCO
3
(d) CaCO
3
5. Which of the following has lowest thermal stability ?
(a)
(b)
(c)
(d)
6. The first (IE
1
) and second (IE
2
) ionisation energies (kJ/mol) of a few
elements designated by Roman numerals are given below. Which of
these would be an alkali metal?
7. The solubilities of carbonates decrease down the magnesium group due
to a decrease in
(a) hydration energies of cations
(b) inter-ionic attraction
Page 3


1. Alkali metals are generally extracted by
(a) reduction methods
(b) double decomposition methods
(c) displacement methods
(d) electrolytic methods
2. Which of the following represents a correct sequence of reducing power
of the following elements?
(a) Li > Cs > Rb
(b) Rb > Cs > Li
(c) Cs > Li > Rb
(d) Li > Rb > Cs
3. Strongest bond is in between
(a) CsF
(b) NaCl
(c) Both (a) and (b)
IE
1
IE
2
(a) I 2372 5251
(b) II 520 7300
(c) III 900 1760
(d) IV 16803 380
(d) None of above
4. A metal salt solution forms a yellow precipitate with potassium
chromate in acetic acid, a white precipitate with dil H
2
SO
4
, but gives no
precipitate with NaCl. The metal salt solution will consist of
(a) PbCO
3
(b) BaCO
3
(c) MgCO
3
(d) CaCO
3
5. Which of the following has lowest thermal stability ?
(a)
(b)
(c)
(d)
6. The first (IE
1
) and second (IE
2
) ionisation energies (kJ/mol) of a few
elements designated by Roman numerals are given below. Which of
these would be an alkali metal?
7. The solubilities of carbonates decrease down the magnesium group due
to a decrease in
(a) hydration energies of cations
(b) inter-ionic attraction
(c) entropy of solution formation
(d) lattice energies of solids
8. KO
2
 (potassium super oxide) is used in oxygen cylinders in space and
submarines because it
(a) absorbs CO
2 
and increases O
2
 content
(b) eliminates moisture
(c) absorbs CO
2
(d) produces ozone
9. Which one of the following salts does not impart colour to the flame ?
(a) KI
(b) LiCl
(c) CaCl
2
(d) MgCl
2
10. Amongst LiCl, RbCl,  and  the compounds with the
greatest and least ionic character respectively are :
(a) LiCl and RbCl
(b) and 
(c) RbCl and 
(d) RbCl and 
11. Which of the following statements about Na
2
O
2 
is not correct?                
     
(a) It is diamagnetic in nature
(b) It is derivative of H
2
O
2
(c) Na
2
O
2
 oxidises Cr
3+
 to  in acid medium.
(d) It is the super oxide of sodium
12. All of the following substances react with water. The pair that gives the
same gaseous product is
Page 4


1. Alkali metals are generally extracted by
(a) reduction methods
(b) double decomposition methods
(c) displacement methods
(d) electrolytic methods
2. Which of the following represents a correct sequence of reducing power
of the following elements?
(a) Li > Cs > Rb
(b) Rb > Cs > Li
(c) Cs > Li > Rb
(d) Li > Rb > Cs
3. Strongest bond is in between
(a) CsF
(b) NaCl
(c) Both (a) and (b)
IE
1
IE
2
(a) I 2372 5251
(b) II 520 7300
(c) III 900 1760
(d) IV 16803 380
(d) None of above
4. A metal salt solution forms a yellow precipitate with potassium
chromate in acetic acid, a white precipitate with dil H
2
SO
4
, but gives no
precipitate with NaCl. The metal salt solution will consist of
(a) PbCO
3
(b) BaCO
3
(c) MgCO
3
(d) CaCO
3
5. Which of the following has lowest thermal stability ?
(a)
(b)
(c)
(d)
6. The first (IE
1
) and second (IE
2
) ionisation energies (kJ/mol) of a few
elements designated by Roman numerals are given below. Which of
these would be an alkali metal?
7. The solubilities of carbonates decrease down the magnesium group due
to a decrease in
(a) hydration energies of cations
(b) inter-ionic attraction
(c) entropy of solution formation
(d) lattice energies of solids
8. KO
2
 (potassium super oxide) is used in oxygen cylinders in space and
submarines because it
(a) absorbs CO
2 
and increases O
2
 content
(b) eliminates moisture
(c) absorbs CO
2
(d) produces ozone
9. Which one of the following salts does not impart colour to the flame ?
(a) KI
(b) LiCl
(c) CaCl
2
(d) MgCl
2
10. Amongst LiCl, RbCl,  and  the compounds with the
greatest and least ionic character respectively are :
(a) LiCl and RbCl
(b) and 
(c) RbCl and 
(d) RbCl and 
11. Which of the following statements about Na
2
O
2 
is not correct?                
     
(a) It is diamagnetic in nature
(b) It is derivative of H
2
O
2
(c) Na
2
O
2
 oxidises Cr
3+
 to  in acid medium.
(d) It is the super oxide of sodium
12. All of the following substances react with water. The pair that gives the
same gaseous product is
(a) K and KO
2
(b) Na and Na
2
O
2
(c) Ca and CaH
2
(d) Ba and BaO
2
13. If NaOH is added to an aqueous solution of  ions, a white
precipitate appears and on adding excess NaOH, the precipitate
dissolves. In this solution zinc exists in the :
(a) both in cationic and anionic parts
(b) there is no zinc left in the solution
(c) cationic part
(d) anionic part
14. The compound A on heating gives a colourless gas and a residue that is
dissolved in water to obtain B. Excess of CO
2
 is bubbled through
aqueous solution of B, C is formed which is recovered in the solid form.
Solid C on gentle heating gives back A. The compound is
(a) CaSO
4
.2H
2
O
(b) CaCO
3
(c) Na
2
CO
3
(d) K
2
CO
3
15. In Castner-Kellner cell for production of sodium hydroxide:
(a) Brine is electrolyzed with Pt electrodes
(b) Brine is electrolyzed using graphite electrodes
(c) Molten sodium chloride is electrolysed
(d) Sodium amalgam is formed at mercury cathode
16. A metal X on heating in nitrogen gas gives Y. Y on treatment with H
2
O
Page 5


1. Alkali metals are generally extracted by
(a) reduction methods
(b) double decomposition methods
(c) displacement methods
(d) electrolytic methods
2. Which of the following represents a correct sequence of reducing power
of the following elements?
(a) Li > Cs > Rb
(b) Rb > Cs > Li
(c) Cs > Li > Rb
(d) Li > Rb > Cs
3. Strongest bond is in between
(a) CsF
(b) NaCl
(c) Both (a) and (b)
IE
1
IE
2
(a) I 2372 5251
(b) II 520 7300
(c) III 900 1760
(d) IV 16803 380
(d) None of above
4. A metal salt solution forms a yellow precipitate with potassium
chromate in acetic acid, a white precipitate with dil H
2
SO
4
, but gives no
precipitate with NaCl. The metal salt solution will consist of
(a) PbCO
3
(b) BaCO
3
(c) MgCO
3
(d) CaCO
3
5. Which of the following has lowest thermal stability ?
(a)
(b)
(c)
(d)
6. The first (IE
1
) and second (IE
2
) ionisation energies (kJ/mol) of a few
elements designated by Roman numerals are given below. Which of
these would be an alkali metal?
7. The solubilities of carbonates decrease down the magnesium group due
to a decrease in
(a) hydration energies of cations
(b) inter-ionic attraction
(c) entropy of solution formation
(d) lattice energies of solids
8. KO
2
 (potassium super oxide) is used in oxygen cylinders in space and
submarines because it
(a) absorbs CO
2 
and increases O
2
 content
(b) eliminates moisture
(c) absorbs CO
2
(d) produces ozone
9. Which one of the following salts does not impart colour to the flame ?
(a) KI
(b) LiCl
(c) CaCl
2
(d) MgCl
2
10. Amongst LiCl, RbCl,  and  the compounds with the
greatest and least ionic character respectively are :
(a) LiCl and RbCl
(b) and 
(c) RbCl and 
(d) RbCl and 
11. Which of the following statements about Na
2
O
2 
is not correct?                
     
(a) It is diamagnetic in nature
(b) It is derivative of H
2
O
2
(c) Na
2
O
2
 oxidises Cr
3+
 to  in acid medium.
(d) It is the super oxide of sodium
12. All of the following substances react with water. The pair that gives the
same gaseous product is
(a) K and KO
2
(b) Na and Na
2
O
2
(c) Ca and CaH
2
(d) Ba and BaO
2
13. If NaOH is added to an aqueous solution of  ions, a white
precipitate appears and on adding excess NaOH, the precipitate
dissolves. In this solution zinc exists in the :
(a) both in cationic and anionic parts
(b) there is no zinc left in the solution
(c) cationic part
(d) anionic part
14. The compound A on heating gives a colourless gas and a residue that is
dissolved in water to obtain B. Excess of CO
2
 is bubbled through
aqueous solution of B, C is formed which is recovered in the solid form.
Solid C on gentle heating gives back A. The compound is
(a) CaSO
4
.2H
2
O
(b) CaCO
3
(c) Na
2
CO
3
(d) K
2
CO
3
15. In Castner-Kellner cell for production of sodium hydroxide:
(a) Brine is electrolyzed with Pt electrodes
(b) Brine is electrolyzed using graphite electrodes
(c) Molten sodium chloride is electrolysed
(d) Sodium amalgam is formed at mercury cathode
16. A metal X on heating in nitrogen gas gives Y. Y on treatment with H
2
O
gives a colourless gas which when passed through CuSO
4
 solution gives
a blue colour. Y is
(a) Mg(NO
3
)
2
(b) Mg
3
N
2
(c) NH
3
(d) MgO
17. The metals A and B form oxide but B also forms nitride when both burn
in air. The A and B are
(a) Cs, K
(b) Mg, Ca
(c) Li, Na
(d) K, Mg
18. The melting point of lithium (181°C) is just double the melting point of
sodium (98°C) because
(a) down the group, the hydration energy decreases
(b) down the group, the ionization energy decreases
(c) down the group the cohesive energy decreases
(d) None of these
19. Which of the following are arranged in increasing order of solubilities?
(a) CaCO
3
 < KHCO
3
 < NaHCO
3
(b) NaHCO
3
 < KHCO
3
 < CaCO
3
(c) KHCO
3
 < NaHCO
3
 < CaCO
3
(d) CaCO
3
 < NaHCO
3
 < KHCO
3
20. Which one of the following does not react with water even under red