Quizzes : Stoichiometry


Q:1. 22.7 ml of N/10 Na2CO3 solution neutralises 10.2 ml of a dilute H2SO4. Then the volume of  water that must be added to 400 ml of same H2SO4  to make
it exactly N/10 is

(A) 245 ml

(B) 484.6 ml

(C) 480 ml

(D) 490.2 ml

Click to See Answer :
Ans: (D)


Q:2. The sulphate of a metal M contains 20% of M. This sulphate is isomorphous with ZnSO4.7H2O. The atomic weight of M is

(A) 12

(B) 24

(C) 36

(D) 48

Click to See Answer :
Ans: (C)


Q:3. 1.12 ml of a gas is produced at STP by the action of 41.2 mg of alcohol, ROH with methyl magnesium iodide. The molecular mass of alcohol is

(A) 16.0

(B) 41.2

(C) 84.2

(D) 156.0

Click to See Answer :
Ans: (C)


Q:4. Rearrange the following (I to IV) in the order of increasing masses and choose the correct answer from (A), (B), (C) and (D) (Atomic mass of N = 14, O = 16, Cu = 63).

(I)   1 molecule of oxygen

(II)  1 atom of nitrogen

(III) 1 × 10–10 gm molecular weight of oxygen

(IV) 1 × 10–10 gm atomic weight of copper

(A) (II) <  (I) < (III) < (IV)

(B) (IV) < (III) < (II) < (I)

(C) (II) < (III) < (I) < (IV)

(D) (III) < (IV) < (I) < (II)

Click to See Answer :
Ans: (A)


Q:5. One mole of calcium phosphide on reaction with excess of water gives

(A) One mole of phosphine

(B) Two moles of phosphoric acid

(C) Two moles of phosphine

(D) One mole of phosphorus pentaoxide

Click to See Answer :
Ans: (C)


Q:6. An aqueous solution of 6.3 gm oxalic acid dihydrate is made upto 250 ml. The volume of 0.1 N NaOH required to completely neutralise 10 ml of this solution is

(A) 40 ml

(B) 20 ml

(C) 10 ml

(D) 4 ml

Click to See Answer :
Ans: (A)


Q:7. If 0.5 mol of BaCl­2 is mixed with 0.2 mol of Na3PO4, the maximum number of moles of Ba3(PO4)2 that can be formed is

(A) 0.7

(B) 0.5

(C) 0.30

(D) 0.10

Click to See Answer :
Ans: (D)


Q:8. 0.5 mol of H2SO4 is mixed with 0.2 mole of Ca(OH)2. The maximum number of mole of CaSO4 formed is

(A) 5

(B) 0.5

(C) 0.4

(D) 1.5

Click to See Answer :
Ans: (A)


Q:9. The hydrated salt Na2SO4.xH2O undergoes 55% loss in weight on heating and becomes anhydrous. The value of x will be

(A) 5

(B) 3

(C) 7

(D) 10

Click to See Answer :
Ans: (D)


Q:10. The percent loss in weight after heating a pure sample of KClO3 (molecular
weight = 122.5) will be

(A) 12.25

(B) 24.50

(C) 39.18

(D) 49.0

Click to See Answer :
Ans: (D)


Q:11. The weight of sodium bromate required to prepare 85.5 ml of 0.672 N solution for cell reaction BrO3 + 6H+ + 6e → Br + 3H2O is

(A) 1.56 gm

(B) 1.45 gm

(C) 1.23 gm

(D) 1.32 gm

Click to See Answer :
Ans: (B)


Q:12. NaIO3 reacts with NaHSO3 according to equation

IO3 + 3HSO3  → I + 3H++ 3SO42–

The weight of NaHSO3 required to react with 100 ml of solution containing 0.58 gm of NaIO3 is

(A) 5.2 gm

(B) 4.57 gm

(C) 2.3 gm

(D) None of these

Click to See Answer :
Ans: (B)


Q:13. 25 ml of H2O2 solution were added to excess of acidified solution of KI and iodine so liberated required 20 ml of 0.1 N Na2S2O3 for titration. The normality H2O2 is ?

(A) 0.02

(B) 0.04

(C) 0.08

(D) 0.03

Click to See Answer :
Ans: (C)


Q:14. A mixture of KBr and NaBr weighing 0.560 gm was treated with aqueous Ag+ and all the bromide ion was recovered as 0.970 gm of pure AgBr. The fraction by weight of KBr in the sample is

(A) 0.25 gm

(B) 0.2378

(C) 0.36

(D) 0.285

Click to See Answer :
Ans: (B)


Q:15. The number of moles of Fe(OH)3 produced by allowing 1 mol of Fe2S3 2 moles of H2O and 3 moles of O2 to react according to the equation

2Fe2S3(s) + 6H2O(l) + 3O2(g) → 4Fe(OH)3(s) + 6S(s) are

(A) 1.26

(B) 2.4

(C) 1.34

(D) 1.43

Click to See Answer :
Ans: (C)


Q:16. The volume in ml of 0.1 N HCl required to react completely with 1.0 gm mixture of Na2CO­3 and NaHCO­3 containing equimolar amounts of the two compounds is

(A) 157.9 ml

(B) 152.6 ml

(C) 200 ml

(D) 98.5 ml

Click to See Answer :
Ans: (A)


Q:17. 25.4 g of iodine and 14.2g of chlorine are made to react completely to yield a mixture of ICl and ICl3. Calcualte the ratio of moles of ICl and ICl3.

(A) 1:1

(B) 1:2

(C) 1:3

(D) 2:3

Click to See Answer :
Ans: (A)


Q:18. Calculate the weight of ion which will be converted into its oxide by the action of 18g of steam on it.

(A) 37.3 gm

(B) 3.73 gm

(C) 56 gm

(D) 5.6 gm

Click to See Answer :
Ans: (A)


Q:19. The hourly energy requirement of an astronaut can be satisfied by the energy released when 34g of sucrose are burnt in his body. How many g of oxygen would be needed to be carried in space capsule to meet his requirement for one day?

(A) 916.2 gm

(B) 91.62 gm

(C) 8.162 gm

(D) 9.162 gm

Click to See Answer :
Ans: (A)


Q:20. 10 ml of a solution of H2O2 labelled ’10 volume’ just decolorises 100 ml of potassium permanganate solution acidified with dilute H2SO4. Calculate the amount of potassium permanganate in the given solution.

(A) 0.1563 gm

(B) 0.563 gm

(C) 5.63 gm

(D) 0.256 gm

Click to See Answer :
Ans: (B)


Click to See All Answers :
1. (D) 2. (C) 3. (C) 4. (A) . (C) 6. (A) 7. (D) 8. (A) 9. (D) 10. (D)

11. (B) 12. (B) 13. (C) 14. (B) 15. (C) 16. (A) 17. (A) 18. (A) 19. (A) 20. (B)