Class 11 Some Basic Concepts of Chemistry MCQ with Answer

Class 11 chemistry MCQs with answers are provided here for Some Basic Concepts of Chemistry. These MCQs are based on the CBSE board curriculum and correspond to the most recent Class 11 chemistry syllabus. By practicing these Class 11 Multiple choice questions, students will be able to quickly review all of the ideas covered in the chapter and prepare for the Class 11 Annual examinations as well as other entrance exams such as NEET and JEE.

Class 11 Chemistry Some Basic Concepts of Chemistry MCQ with Answer

Q1. What will be the molarity of a solution, which contains 5.85g of NaCl(s) per 500mL?

1. 4mol L^-1
2. 20mol L^-1
3. 0.2mol L^-1
4. 2mol L^-1

Q2. Zinc sulphate contains 22.65% zinc and 43.9% water of crystallisation. If the law of constant proportions is true
then the weight of zinc required to produce 20g of the zinc sulphate crystals will be:

1. 45.3g.
2. 4.53g.
3. 0.453g.
4. 453g.

Q3. What will be the molality of the solution made by dissolving 10g of NaOH in 100g of water?

1. 2.5m.
2. 5m.
3. 10m.
4. 1.25m.

Q4. Which of the following statements is/ are incorrect?

1. The weight of a substance can be determined very accurately by using an analytical balance.
2. Volume is denoted in dm units.
3. Density of a substance is its amount present per unit volume.
4. Candela is the luminous intensity, that emits monochromatic radiation of frequency, 540 × 10¹² Hz.

Q5. One mole of oxygen gas at STP is equal to _. 1 Mark

1. 6.022 × 10 molecules of oxygen.
2. 6.022 × 10 atoms of oxygen.
3. 16g of oxygen.
4. 32g of oxygen.

Q6. 0.2429g sample of potassium is heated in oxygen, 0.440g of a crystalline compound is obtained. What is the
formula of this compound?

1. KO
2. K₂O
3. KO₂
4. KO₃

Q7. What is the mass percent of carbon in carbon dioxide?

1. 0.034%
2. 27.27%
3. 3.4%
4. 28.7%

Q8. 1g of M₂CO₃ on treatment with excess HCl produces 0.01186 moles of CO₂ The molar mass of M₂CO₃ in g mor^-1
is:

1. 1186
2. 84.3
3. 118.6
4. 11.86

Q9.

Q10. The result reported in the following multiplication of significant figures,
2.5 × 1.25 = 3.125 should be:

1. 3.125
2. 3.1
3. 3.12
4. 3.10

Q12. What is mass silicon in 100g of sodium silicate, Na₂SiO₃ ?

1. 16.7%
2. 23.0%
3. 28.0%
4. 82.0%

Q13. The number of atoms present in one mole of an element is equal to Avogadro number. Which of the following
element contains the greatest number of atoms?

1. 4g He
2. 46g Na
3. 0.40g Ca
4. 12g He

Q14. Which of the following solutions have the same concentration?

1. 20g of NaOH in 200mL of solution.
2. 0.5mol of KCl in 200mL of solution.
3. 40g of NaOH in 100mL of solution.
4. 20g of KOH in 200mL of solution.

Q15. How many number of aluminium ions are present in 0.051g of aluminium oxide?

1. 6.023 × 10²³ ions.
2. 3 ions.
3. 6.023 × 10²⁰ ions.
4. 9 ions.

Q18. The solution of A and B are 0.1 and 0.2 molar in a substance. If 100ML of ‘A’ are mixed with 25mL of B and there
is no change in volume, then the final molarity of solution is:

1. 0.15M
2. 0.18M
3. 0.12M
4. 0.30M

Q19. One of the statements of Dalton’s atomic theory is given below:
“Compounds are formed when atoms of different elements combine in a fixed ratio”
Which of the following laws is not related to this statement?

1. Law of conservation of mass.
2. Law of definite proportions.
3. Law of multiple proportions.
4. Avogadro law.

Q21. If the density of a solution is 3.12g mL^-1 , the mass of 1.5mL solution in significant figures is _.

1. 4.7g
2. 4680 × 10–3gClick To View The Answer
3. 4.680g
4. 46.80g

Q22. The weight of iron which will be converted into its oxide (Fe₃ O₄ ) by the action of 18g of steam on it will be
(Atomic weight of Fe = 56).

1. 168g.
2. 84g.
3. 42g.
4. 21g.

Q23. How many number of molecules and atoms respectively are present in 2.8L of a diatomic gas at STP?

1. 6.023 × 10²³ , 7.5 × 10²³
2. 6.023 × 10²³ , 15 × 10²²
3. 7.5 × 10 , 15 × 10²²
4. 15 × 10 , 7.5 × 10²³

Q25. A gas is found to have the formula (CO)x . Its vapour density is 70. The value of x will be:

1. 7
2. 4
3. 5
4. 6

Q27. The mass of one mole a chloride formed by metal ‘X’ is 111.0g. Which one could be formula of chloride?

1. XCl
2. XCl₂
3. XCl₃
4. XCl₄

Q28. A measured temperature on Fahrenheit scale is 200°F. What will this reading be on Celsius scale?

1. 40°C
2. 94°C
3. 93.3°C
4. 30°C

Q29. Which law states that if two elements can combine to form more than one compound, the masses of one
element that combine with a fixed mass of other element, are in the ratio of small whole numbers?

1. Avogadro’s law.
2. Law of definite composition.
3. Law of multiple proportions.
4. Gay Lussac’s law of gaseous volumes.

Q30. Which set of figures will be obtained after rounding upto three significant figures 1.386, 4.334, 2.808?

1. 1.39, 4.34, 2.809
2. 1.39, 4.33, 2.81
3. 1.38, 4.34, 2.800
4. 1.39, 4.34, 2.80