SOME BASIC CONCEPTS OF CHEMISTRY PART-3

NEET UG, JEE Main Chemistry questions: Online Multiple Choice Questions (MCQs) with answers for NEET and JEE Main aspirants, Chemistry Practice questions, MCQs, Past Year Questions (PYQs), NCERT Questions, Question Bank, Class 11 and Class 12 Questions, NCERT Exemplar Questions ... 

1. For the reaction, 𝐴 + 2𝐵⟶𝐶,5 moles of 𝐴 and 8 moles of 𝐵 will produce: 

a) 5 moles of 𝐶 

b)4 moles of 𝐶 

c) 8 moles of 𝐶 

d)13 moles of 𝐶 

2. Which sample contains the largest number of atoms? 

a) 1 mg of C4H10 

b)1 mg of N2 

c) 1 mg of Na 

d)1 mL of water 

3. An aromatic hydrocarbon with empirical formula C5H4 on treatment with concentrated H2SO4 gave a monosulphonic acid. 0.104 g of the acid required 10 mL of N 20 NaOH for complete neutralisation. The molecular formula of hydrocarbon is 

a) C5H4 

b)C10H8 

c) C15H12 

d)C20H16 

4. If isotopic distribution of C-12 and C-14 is 98% and 2% respectively then the number of C-14 atoms in 12 g of carbon is 

a) 1.032 × 1022 

b)3.01 × 1022 

c) 5.88 × 1023 

d)6.023 × 1023 

5. Zinc sulphate contains 22.65% of zinc and 43.9% of water of crystallization. If the law of constant proportions is true then the weight of zinc required to produce 20 g of the crystals will be 

a) 45.3 g 

b)4.53 g 

c) 0.453 g 

d)453 g 

6. The number of gram molecules of chlorine in 6.02 × 1025 hydrogen chloride molecules is 

a) 10 

b)100 

c) 50 

d)5 

7. The net charge on ferrous ion is: 

a) +2 

b)+3 

c) +4 

d)+5 

8. H2O2 solution used for hair bleaching is sold as a solution of approximately 5.0 g H2O2 Per 100 mL of the solution. The molecular weight of H2O2 is 34. The molarity of this solution is approximately: 

a) 3.0 

b)1.5 

c) 0.15 

d)4.0 

9. 4.6 × 1022 atoms of an element weigh 13.8 g. The atomic weight of element is 

a) 290 

b)180 

c) 34.4 

d)10.4 

10. The weight of 50% (wt./wt.) solution of HCl required to react with 100 g of CaCO3 would be: 

a) 73 g 

b)100 g 

c) 146 g 

d)200 g 

11. An element, 𝑋 has the following isotopic composition 200𝑋:90% 199𝑋:8.0% 202𝑋:2.0% The weighted average atomic mass of the naturally occurring element 𝑋 is closed to 

a) 200 u 

b)210 u 

c) 202 u 

d)199 u 

12. Law of constant composition is same as the law of 

a) Conservation of mass 

b)Conservation of energy 

c) Multiple proportion 

d)Definite proportion 

13. One atom of an element 𝑋 weight 6.643 × 10―23g. number of moles of atom in 20 kg is 

a) 140 

b)150 

c) 250 

d)500 

14. The reaction, 2C + 2O2⟶2CO2is carried out by taking 24 g carbon and 96 g O2. Which one is limiting reagent? 

a) C 

b)O2 

c) CO2 

d)None of these 

15. 1000 g aqueous solution of CaCO3 contains 10 g of calcium carbonate. Concentration of solution is: 

a) 10 ppm 

b)100 ppm 

c) 1000 ppm 

d)10000 ppm 

16. The maximum amount of BaSO4 precipitated on mixing 20 mL of 0.5 𝑀 BaCl2 with 20 mL of 1 𝑀 H2SO4 is: 

a) 0.25 mole 

b)0.5 mole 

c) 1 mole 

d)0.01 mole 

17. The percentage of an element 𝑀 is 53 in its oxide of molecular formula M2O3. Its atomic mass is about 

a) 45 

b)9 

c) 18 

d)27 

18. H3BO3 is: 

a) Monobasic and weak Lewis acid 

b)Monobasic and weak Bronsted acid 

c) Monobasic and strong Lewis acid 

d)Tribasic and weak Bronsted acid 

19. A sample of peanut oil weighing 1.5763 g is added to 25 mL of 0.4210 𝑀 KOH after saponification is complete 8.46 mL of 0.2732 𝑀 H2SO4 is needed to neutralise excess KOH. The saponification number of peanut oil is: 

a) 209.6 

b)108.9 

c) 98.9 

d)218.9 

20. What quantity of ammonium sulphate is necessary for the production of 𝑁𝐻3 gas sufficient to neutralize a solution containing 292 g of 𝐻𝐶𝑙? [𝐻𝐶𝑙 = 36.5,(𝑁𝐻4 )2 𝑆𝑂4 = 132,𝑁𝐻3 = 17] 

a) 272 g 

b)403 g 

c) 528 g 

d)1056 g

Answer Key

1- B , 2- D,  3- C, 4-A , 5-B, 6-B, 7-A, 8-B, 9-B, 10-C, 

11-A, 12-D, 13-D, 14-A, 15-D, 16-D, 17-D, 18-A, 19-A, 20-C 

Read 👉👉👉  SOME BASIC CONCEPTS OF CHEMISTRY PART-4

Read 👉👉👉  SOME BASIC CONCEPTS OF CHEMISTRY PART-2