NEET Chemistry The S Block Elements MCQs Set 02

Question:  On heating which of the following releases CO₂ most easily?

• a) MgCO₃
• b) CaCO₃
• c) K₂CO₃ 
• d) Na₂CO₃

Answer:  MgCO₃

Question: The function of "Sodium pump" is a biological process operating in each and every cell of all animals. Which of the following biologically important ions is also a constituent of the pump?

• a) Fe²⁺
• b) Ca²⁺ 
• c) Mg²⁺ 
• d) K⁺

Answer:  K⁺

Question: Solubility of the alkaline earth's metal sulphates in water decreases in the sequence

• a) Ba > Mg > Sr > Ca
• b) Mg > Ca > Sr > Ba
• c) Ca > Sr > Ba > Mg
• d) Sr > Ca > Mg > Ba

Answer: Mg > Ca > Sr > Ba

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

• a) Li
• b) Na
• c) Rb
• d) K

Answer: Li

Question: Equimolar solutions of the following substances were prepared separately. Which one of these will record the highest pH value?

• a) LiCl
• b) BeCl₂
• c) BaCl₂  
• d) AlCl₃

Answer:  BaCl₂  

Question: Which of the following compounds has the lowest melting point?

• a) CaF₂  
• b) CaCl₂
• c) CaBr₂  
• d) CaI₂

Answer:  CaI₂

Question: Which one of the following is present as an active ingredient in bleaching powder for bleaching action?

• a) CaCl₂  
• b) CaOCl₂
• c) Ca(OCl)₂ 
• d) CaO₂Cl

Answer:  Ca(OCl)₂ 

Question: Which of the following statements is incorrect ?

• a) Aluminium reacts with excess NaOH to give Al(OH)₃
• b) NaHCO₃ on heating gives Na₂CO₃
• c) Pure sodium metal dissolves in liquid ammonia to give blue solution
• d) NaOH reacts with glass to give sodium silicate

Answer:  Aluminium reacts with excess NaOH to give Al(OH)₃

Question:   Match list-I with list-II for the composition of substances and select the correct answer using the code given below the lists

• a) (A) (B) (C) (D) (i) (ii) (iii) (iv)
• b) (A) (B) (C) (D) (iv) (iii) (ii) (i)
• c) (A) (B) (C) (D) (iii) (iv) (i) (ii)
• d) (A) (B) (C) (D) (ii) (iii) (iv) (i)

Answer: (A) (B) (C) (D) (ii) (iii) (iv) (i)

Question: Which of the following alkaline earth metal sulphates has hydration enthalpy higher than the lattice enthalpy ?

• a) CaSO₄  
• b) BeSO₄
• c) BaSO₄  
• d) SrSO₄

Answer:  BeSO₄

Question: 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) Ionization energy
• d) Electronegativity

Answer: Solubility of their hydroxides in water

More Questions...........................................

Question: Which one of the following compounds is a peroxide ?

• a) KO₂ 
• b) BaO₂
• c) MnO₂  
• d) NO₂

Answer:  BaO₂

Question:  The compound A on heating gives a colourless gas and a residue that is dissolved in water to obtain B. Excess of CO₂ 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) CaCO₃  
• b) Na₂CO₃
• c) K₂CO₃
• d) CaSO₄.2H₂O

Answer:  CaCO₃  

Question: Which of the following oxides is not expected to react with sodium hydroxide ?

• a) CaO
• b) SiO₂
• c) BeO
• d) B₂O₃

Answer: CaO

Question: The alkali metals from salt-like hydrides by the direct synthesis at elevated temperature. The thermal stability of these hydrides decreases in which of the following orders ?

• a) LiH > NaH > KH > RbH > CsH
• b) CsH > RbH > KH > NaH > LiH
• c) KH > NaH > LiH > CsH > RbH
• d) NaH > LiH > KH > RbH > CsH

Answer: LiH > NaH > KH > RbH > CsH

Question: In which of the following the hydration energy is higher than the lattice energy ?

• a) SrSO₄  
• b) BaSO₄
• c) MgSO₄ 
• d) RaSO₄

Answer:  MgSO₄ 

Question:  The correct order of increasing thermal stability of K₂CO₃, MgCO₃, CaCO₃ and BeCO₃ is

• a) K₂CO₃< MgCO₃< CaCO₃< BeCO₃  
• b) BeCO₃< MgCO₃< K₂CO₃< CaCO₃
• c) BeCO₃< MgCO₃< CaCO₃< K₂CO₃  
• d) MgCO₃< BeCO₃< CaCO₃< K₂CO₃

Answer:  BeCO₃< MgCO₃< CaCO₃< K₂CO₃  

Question: The correct order of the mobility of the alkali metal ions in aqueous solution is

• a) Li⁺ > Na⁺ > K⁺ > Rb⁺
• b) Na⁺ > K⁺ > Rb⁺ > Li⁺ 
• c) K⁺ > Rb⁺ > Na⁺ > Li⁺
• d) Rb⁺ > K⁺ > Na⁺ > Li⁺

Answer:  Rb⁺ > K⁺ > Na⁺ > Li⁺

Question: 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

Answer: Sodium amalgam is formed at mercury cathode

Question:  In the replacement reaction

The reaction will be most favourable if M happens to be

• a) Na
• b) K
• c) Rb
• d) Li

Answer: Rb

Question: The solubility in water of sulphate down the Be group is Be > Mg > Ca > Sr > Ba. This is due to

• a) Decreasing lattice energy
• b) High heat of solvation for smaller ions like Be²⁺
• c) Increase in melting points
• d) Increasing molecular weight

Answer:  High heat of solvation for smaller ions like Be²⁺

Question:  The sodium is made by the electrolysis of a molten mixture of about 40% NaCl and 60% CaCl₂ because

• a) Ca⁺⁺ can displace Na from NaCl 
• b) This mixture has a lower melting point than NaCl
• c) CaCl₂ helps in conduction of electricity
• d) Ca⁺⁺ can reduce NaCl to Na

Answer: This mixture has a lower melting point than NaCl

Question: Identify the correct statement

• a) Plaster of Paris can be obtained by hydration of gypsum
• b) Plaster of Paris is obtained by partial oxidation of gypsum
• c) Gypsum contains a lower percentage of calcium than Plaster of Paris
• d) Gypsum is obtained by heating Plaster of Paris

Answer: Gypsum contains a lower percentage of calcium than Plaster of Paris

Question: When a substance (a) reacts with water it produces a combustible gas (b) and a solution of substance (c) in water. When another substance (d) reacts with this solution of (c), it also produces the same gas (b) on warming but (d) can produce gas (b) on reaction with dilute sulphuric acid at room temperature. Substance (a) imparts a deep golden yellow colour to a smokeless flame of Bunsen burner. Then (a), (b), (c) and (d) respectively are

• a) Ca, H₂, Ca(OH)₂, Sn
• b) K, H₂, KOH, Al 
• c) Na, H₂, NaOH, Zn  
• d) CaC₂, C₂H₂, Ca(OH)₂, Fe

Answer:  Na, H₂, NaOH, Zn  

Question: Calcium is obtained by

• a) Reduction of calcium chloride with carbon
• b) Electrolysis of molten anhydrous calcium chloride
• c) Roasting of limestone
• d) Electrolysis of solution of calcium chloride in H₂O

Answer: Electrolysis of molten anhydrous calcium chloride

Question: Among the oxides of group 2, least basic is

• a) MgO
• b) CaO
• c) SrO
• d) BaO

Answer: MgO

Question: Which is not the compound of sodium?

• a) Chile salt petre
• b) Salt petre
• c) Glauber's salt
• d) Soda ash

Answer: Salt petre

Question: Sodium is usually kept under

• a) Alcohol
• b) Kerosene oil
• c) Water
• d) Petrol

Answer: Kerosene oil

Question: Which one of the following statements concerning the compounds of Lithium is false?

• a) The hydroxide, carbonate, nitrate, decompose to give the oxide on heating
• b) It is the most electronegative among alkali metals
• c) The hydrogen carbonate cannot be isolated as a stable solid
• d) It forms a peroxide but not superoxide

Answer: It forms a peroxide but not superoxide

Question: The thermal stability of alkaline earth metal carbonates increases from Be to Ba. This is because

• a) Covalent nature decreases and Ionic nature increases
• b) Lattice energy increases
• c) Electropositive nature decreases
• d) None of these

Answer: Covalent nature decreases and Ionic nature increases