redox-and-equivalent-concept-quiz-9

Redox And Equivalent Concept Quiz-9

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 oxidation number of N in NH₃ is :

•  -3
•  +3
•  Zero
•  5

Solution
(a) a+3 × (+1)=0 ∴a= -3  

Q2.A 0.50 M solution of KI reacts with excess of H₂ SO₄ and KIO₃ solutions according to the equation, 6H⁺ +5I^- +IO₃^- ⟶3I₂+3H₂ O. Which of the following statements is true?

•  200 mL of the KI solution reacts with 0.10 mole KIO₃.
•  100 mL of the KI solution reacts with 0.060 M of H₂ SO₄.
•  0.5 litre of the KI solution produces 0.15 mole of I₂
•  None of the above

Solution

(c) 5 mole I^- gives 3 mole I₂

Q3. In the conversion of Br₂ to BrO₃^-, the oxidation number of Br changes from  

•  Zero to +5
•  +1 to +5
•  Zero to -3
•  +2 to +5

Solution
(a) Bromine has zero oxidation state because it is in free state. 0 Br₂⟶BrO₃^- Let the oxidation number of Br in BrO₃^- is x. x+(-2×3)=-1 x+(-6)= -1 x=+6-1 x=+5 So, oxidation number changes from 0 to +5.

Q4. LiAIH₄ is used as :

•  Oxidising agent
•  Reducing agent
•  A mordant
•  Water softner

Solution
(b) H in LiAIH₄ has −1 ox.no. and thus, easily oxidized.

Q5.Solution of sodium metal in liquid NH₃ is strongly reducing due to the presence of :

•  Sodium atoms
•  Solvated electrons
•  NaOH
•  Sodium amide

Solution
 

Q6. The oxidation number of phosphorus in PO₄^3-,P₄ O₁₀ and P₂ O₇^4- is :

•  +3
•  +2
•  -3
•  +5

Solution
(d) Find oxidation number of P in each.  

Q7.In the reaction, VO+Fe₂ O₃ ⟶FeO+V₂ O₅. The eq.wt. of V₂ O₅ is equal to its :

•  mol. wt.
•  mol. wt./8
•  mol. wt./6
•  None of these

Solution

(c) 2V²⁺ ⟶V₂⁵⁺+6e

Q8.Ozone tails mercury. The reaction is ….of Hg.

•  Reduction
•  Oxidation
•  Substitution
•  None of these

Solution
(b) Hg+O₃ ⟶HgO+O₂  

Q9.A student states that heating of limestone is an oxidation process, the reason he gives that an oxide of the metal is produced on heating. Which one is correct?

•  The statement and reason are true
•  The statement and reason are wrong
•  The statement is true but the reason is false
•  None of the above

Solution

Q10. The reaction; H₂ S+H₂ O₂ ⟶2H₂ O+S shows :

•  Acidic nature of H₂ O₂
•  Alkaline nature of H₂ O₂
•  Oxidising action of H₂ O₂
•  Reducing action of H₂ O₂

Solution

(c) H₂ O₂ oxidises S^2- to S⁰.