NEET Chemistry Chapter Wise Mock Test – s-Block Elements
Question 1:
Alkali metals impart colour to Bunsen flame due to
(a) low ionisation energy
(b) low melting point
(c) their softness
(d) the presence of one electron in the outer most shell
Question 2:
Which of the following are arranged in correct increasing order of solubilities?
(a)CaC03 < KHCOg < NaHCO3
(b)NaHCO3< KHCOg < CaC03
(c)KHCO3 < NaHCOg < CaCO3
(d)CaCO3 < NaHCOg < KHCO3
Question 3:
Question 4:
The alkali metals form salt-like hydride by the direct synthesis at elevated temperature. The thermal stability of these hydrides decreases in which of the following orders?
(a) CsH > RbH > KH > NaH > LiH
(b) KH > NaH > LiH > CsH > RbH
(c) NaH > LiH > KH > RbH > CsH
(d) LiH > NaH > KH > RbH > CsH
Question 5:
Mg burns in CO to produce
(a)MgO+ CO
(b)Mg02
(c)MgO + C
(d)MgCOg
Question 6:
Which pair of the following chlorides do not impart colour to the flame?
(a) BeCI2 and SrCI2
(b) BeCI2and MgCI2
(c) CaCI2 and BaCI2
(d) BaCI2 and SrCI2
Question 7:
Shine at freshly cut sodium is
(a) due to oscillation of free electrons
(b) due to weak metallic bonding
(c) due to absorption of light in crystal lattice
(d) due to the presence of free valency at the surface
Question 8:
In the alkaline earth metals, the element forming predominantly covalent compound is
(a) Ca
(b) Sr
(c) Mg
(d) Be
Question 9:
A metal M readily forms its sulphate MS02 which is water soluble. It forms its oxide MO which becomes inert on heating. It forms its insoluble hydroxide M(OH)2 which is soluble in NaOH. Then M is
(a) Be
(b) Ba
(c) Ca
(d) My
Question 10:
BaS04 is insoluble in water due to its
(a) high hydration energy
(b) high lattice energy
(c) high ionisation energy
(d) high kinetic energy
Question 11:
Question 12:
The correct sequence of increasing covalent character is represented by
(a) LiCI < NaCI < BeCI2
(b) BeCI2 < NaCI < LiCI
(c)NaCI < LiCI < BeCI2
(d) BeCI2 < LiCI < NaCI
Question 13:
Amphoteric hydroxides react with both alkalies and acids. Which of the following group 2 metal hydroxides is soluble in sodium hydroxide?
(a) Be(OH)2
(b) Mg(OH)2
(c) Ca(OH)2
(d) Ba(OH)2
Question 14:
Question 15:
Which is the weakest reduction agent?
(a) Na
(b) K
(c) Rb
(d) Li
Question 16:
Among the alkali metals, caesium is the most reactive because
(a) its incomplete shell is nearest to the nucleus
(b) it has a single electron in the valence shell
(c) it is the heaviest alkali metal
(d) the outermost electron is more loosely bound than the . outermost electron of the other alkali metals
Question 17:
Which of the following statements is true about Ca(OH)2?
(a) It is used in the preparation of bleaching powder
(b) It is a light blue solid
(c) It does not possess disinfectant property
(d) It is used in the manufacture of cement
Question 18:
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 electron
(b) sodium ion
(c) sodium amide
(d) ammoniated sodium ion
Question 19:
A solution of sodium metal in liquid NH3 is strongly reducing due to the presence of
(a)sodium ions
(b)sodium amide
(c)solvated electrons
(d)sodium hydride
Question 20:
Question 21:
Sodium peroxide which is a yellow solid, when exposed to air becomes white due to the formation of
(a)H202
(b) Na20
(c) Na20and03
(d) NaOH and Na2C03
Question 22:
When sodium is heated with moist air, the product obtained is
(a) Na202
(b) Na2C03
(c) NaOH
(d) Na20
Question 23:
The alkali metal that reacts with nitrogen directly to form nitride is
(a) Li
(b) K
(c) Na
(d) Rb
Question 24:
The correct order of increasing thermal stabilities of K2C03, MgC03, CaC03 and BeC03 is
(a) BeC03 < MgC03 < K2C03 < CaC03 .
(b) BeC03 < MgC03 < CaC03 < K2C03
(c) MgC03 < BeC03 < CaC03 < K2C03
(d) K2C03 < MgC03 < CaC03 < BeC03
Question 25:
Question 26:
A solid compound X on heating gives C02 gas and a residue. The residue mixed with water forms Y. On passing an excess of C02through Y in water, a clear solution, Z. On boiling Z, compound, X is reformed. The compound X is
(a) Ca(HC03)2
(b) CaC03
(c) Na2C03
(d) K2C03
Question 27:
Sodium thiosulphate is prepared by
(a)boiling Na2S03 solution with S in alkaline medium
(b)reducing Na2S04 solution with H2S
(c)boiling Na2S03 solution with S in acidic medium
(d)neutralising H2S203 solution with NaOH
Question 28:
Fire extinguisher contain H2SO4 and
(a) Na2C03
(b) NaHC03
(c) CaC03
(d) All of these
Question 29:
Question 30:
K2C03 cannot be prepared by Solvay ammonia process because
(a) K2C03 is fairly soluble in water
(b) it has no water of crystallisations
(c) KHC03is highly soluble in water
(d) K2C03 decomposes in H20
Question 31:
When washing soda is heated
(a) CO is released
(b) CO+ C02 is released
(c) C02 is released
(d) water vapour is released
Question 32:
Microcosmic salt is
(a) Na(NH4)HP4.4H20
(b) Na(NH4)H20
(c) Na(NH3)HP4.4H20
(d) K(NH4)HP03-2H20
Question 33:
Fusion mixture is
(a) KHS04+ Na2S03
(b) K2C03 + NaHS04
(c) KHS04 + NaHS04
(d) K2C03+ Na2C03
Question 34:
Several blocks of magnesium are fixed to the bottom of a ship to
(a) keep away the sharks
(b) make the ship lighter
(c) prevent action of water and salt
(d) prevent puncturing by under-sea rocks
Question 35:
The pair whose both species are used in antiacid medicinal preparations is
(a) NaHC03 and Mg(QH)2
(b) Na2C03 and Ca(HC03)2
(c) Ca(HC03)2 and Mg(OH)2
(d) Ca(OH)2 and NaHC03
Direction (Q. Nos. 36-37) In the following questions more than one of the answers given may be correct. Select the correct answer and mark it according to the codes.
Codes
(a) 1,2 and 3 are correct
(b) 1 and 2 are correct
(c) 2 and 4 are correct
(d) 1 and 3 are correct
Question 36:
Identify the correct formula of halides of alkaline earth metals from the following
(a) BaCI2 -2H20
(b) BaCI2 -4H20
(c) CaCI2 -6H20
(d)SrCI2 -4H20
Question 37:
Highly pure dilute solution of sodium in liquid ammonia
(a)shows blue colour
(b) exhibits electrical conductivity
(c) produces sodium amide
(d)produces hydrogen gas
Question 38:
Direction (Q. Nos. 39-42) Each oj^th^sequestions contains two statements : Assertion and kedsoh. Each of these questions also has four alternative choices, only one of which is the correct answer. You have to select one of the codes (a),(b) , (c) and (d) given below.
(a) .Assertion is true, Reason is true; Reason is a correct explanation for Assertion
(b) Assertion is true, Reason is true; Reason is not a correct explanation for Assertion
(c) Assertion is true, Reason is false
(d) Assertion is false, Reason is true
Question 39:
Assertion Group 1 (IA) elements are known as the alkali elements.
Reason s-orbital can accommodate only two electrons.
Question 40:
Assertion Radium is most abundant s-block element.
Reason Except francium (Fr), all s-biock elements are non-radioactive in nature.
Question 41:
Assertion The first ionisation enthalpy of Be is greater than that of B.
Reason 2p-orbtial is lower in energy than 2s-orbital.
Question 42:
Assertion K, Rb and Cs form superoxides.
Reason The stability of the superoxides increases from K to Cs due to decrease in lattice energy.
Question 43:
Question 44:
Solubility of the alkaline earth’s metal sulphates in water decreases in the sequence
(a) Mg > Ca > Sr > Ba
(b) Ca > Sr > Ba > Mg
(c) Sr > Ca > Mg > Ba
(d) Ba > Mg > Sr > Ca
Question 45:
Question 46:
Which one of the alkali metals forms only, the normal oxide, M20 on heating in air?
(a) Rb
(b) K
(c) Li
(d) Na
Question 47:
Property of the alkaline earth metals that increases with their atomic number
(a) solubility of their hydroxides in water
(b) solubility of their sulphates in water
(c) ionisation energy
(d) electronegativity
Question 48:
Which of the following alkaline earth metal sulphate
has hydration enthalpy higher than the lattice enthalpy?
(a) CaS04
(b) BeS04
(c) BaS04
(d) SrS04
Question 49:
In which process, fused sodium hydroxide is electrolysed for extraction of sodium?
(a) Castner’s process
(b) Cyanide process
(c) Down’s process
(d) Both (a) and (c)
Question 50:
Which of the following carbonates is the most stable?
(a) MgCOg
(b) CaC03
(c) SrC03
(d) BaCO3
Answers:
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