s-block-quiz-4

S-Block Quiz-4

Dear Readers,

The one subject in NEET which is candidates who can easily attain good marks is Chemistry. That's the reason, often, one doesn’t pay notice and choose to compromise it. But if one wants to rank above others, the tip is to be thorough with NEET chemistry concepts. The understanding of reactions and definite basic understanding is what requires major attention in Chemistry but once done it only gets simpler from there. The main focus on the to-do list should be on getting a hang of the NCERT syllabus of NEET chemistry..

Q1. The non-metal which is not affected by NaOH:

•  C
•  Si
•  P
•  S

Solution
(a) Carbon has no reaction with NaOH.  

Q2.Which of the following metals has stable carbonates?

•  Al
•  Si
•  Mg
•  Na

Solution

(d) When carbonates are heated, they decompose to form the oxide. Sodium carbonate and potassium carbonate do not decompose. The carbonate become more difficult to decompose as we go down the 1st group

Q3. Shine at freshly cut sodium is because of 

•  Due to oscillation of free electrons
•  Due to weak metallic bonding
•  Due to by absorption of light in crystal lattice
•  Due to presence of free valency at the surface

Solution
(a)Due to oscillation of free electrons

Q4. Milk of magnesia is:

•  Mg(OH)₂
•  Ca(OH)₂
•  Ba(OH)₂
•  None of these

Solution
(a) A suspension of Mg(OH)₂ in water is used as antacid under the name of milk of magnesia.

Q5.One mole of magnesium nitride on the reaction with an excess of water gives

•  One mole of NH₃
•  Two moles of NH₃
•  One mole of HNO₃
•  Two moles of HNO₃

Solution
  (b) One mole of magnesium nitride on the reaction with an excess of water gives two moles of ammonia. Mg₃ N₂+6H₂ O →3Mg(OH)₂+2NH₃ 

                  1 mol                                         2 mol  

Q6. The alkali metal that reacts with nitrogen directly to form nitride is

•  Li
•  K
•  Na
•  Rb

Solution
(a) 6Li+N₂→ 2Li₃ N lithium nitride  

Q7.In certain matters, lithium differs from other alkali metals, the main reason for this is:

•  Small size of lithium atom and Li⁺ ion
•  Extremely high electropositivity of Li
•  Greater hardness of Li
•  Hydration of Li⁺ ion

Solution

(a) It is a reason for given fact.

Q8.Sodium carbonate on heating gives:

•  Water vapours
•  Carbon dioxide
•  Carbon dioxide + water vapour
•  None of the above

Solution
(d) Na₂ CO₃ is thermally stable.  

Q9.Which of the following is an epsom salt?

•  2CaSO₄ .H₂ O
•  MgSO₄ .7H₂ O
•  MgSO₄ .2H₂ O
•  BaSO₄ .2H₂ O

Solution

(b) Magnesium sulphate heptahydrate [MgSO₄ .7H₂ O] is called epsom salt.

Q10. Which of the following hydroxides is insoluble in water?

•  Ba(OH)₂
•  Ca(OH)₂
•  Be(OH)₂
•  Mg(OH)₂

Solution

(c) The solubility of hydroxides of alkaline earth metals in water increases on moving down the group