Students of class 11 Chemistry should refer to MCQ Questions Class 11 Chemistry Some Basic Concepts of Chemistry with answers provided here which is an important chapter in Class 11 Chemistry NCERT textbook. These MCQ for Class 11 Chemistry with Answers have been prepared based on the latest CBSE and NCERT syllabus and examination guidelines for Class 11 Chemistry. The following MCQs can help you to practice and get better marks in the upcoming class 11 Chemistry examination

Chapter 1 Some Basic Concepts of Chemistry MCQ with Answers Class 11 Chemistry

MCQ Questions Class 11 Chemistry Some Basic Concepts of Chemistry provided below have been prepared by expert teachers of grade 11. These objective questions with solutions are expected to come in the upcoming Standard 11 examinations. Learn the below provided MCQ questions to get better marks in examinations.

Question. Which of the following pairs of gases contains the same number of molecules ?
(a) 16 g ofO₂ and 14 g of N₂
(b) 8 g ofO₂ and 22 g of CO₂
(c) 28 g of N₂ and 22 g of CO₂
(d) 32 g ofO₂ and 32 g of N₂

Question. The mass of potassium dichromate crystals required to oxidise 750 cm³ of 0.6 M Mohr’s salt solution is (Given, molar mass : Potassium dichromate = 294, Mohr’s salt = 392) 
(a) 0.49 g
(b) 0.45 g
(c) 22.05 g
(d) 2.2 g

Question. The equivalent weight of H₃ PO₂ ,when it disproportionates into PH₃ and H₃PO₄, is
(a) 82
(b) 61.5
(c) 33
(d) 20.5

Question. How many moles of magnesium phosphate,Mg₃ (PO₄ )₂ will contain 0.25 mole of oxygen atoms?
(a) 0.02
(b) 3.125 × 10 ⁻²
(c) 1.25 × 10 ⁻²
(d) 2.5 × 10 ⁻²

Question. Potassium selenate is isomorphous with potassium sulphate and contains 50.0% of Se. Find the atomic weight of Se.
(a) 47.33
(b) 71
(c) 142
(d) 284

Question. Two oxides of metal were found to contain 31.6% and 48% of oxygen respectively. If the formula of first is represented byM₂O₃, then formula of second is
(a) MO₃
(b) MO₂
(c) M₂O
(d) M₂ O₂ 

Question. Number of atoms in the following samples of substances is largest in 
(a) 4.0 g of hydrogen
(b) 70.0 g of chlorine
(c) 127.0 g of iodine
(d) 48.0 g of magnesium

Question. The total number of electrons present in 18 mL of water (density of water is 1 gmL⁻¹) is
(a) 6.02 10 × 23
(b) 6.02 10 × 23
(c) 6.02 10 × 24
(d) 6.02 10 × 25

Question. 3g of an oxide of a metal is converted to chloride completely and it yielded 5 g of chloride.The equivalent weight of the metal is
(a) 33.25
(b) 3.325
(c) 12
(d) 20

Question. If we consider that 1/6 in place of 1/12, mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of a substance will
(a) to be a function of the molecular mass of the substance
(b) remain unchanged
(c) increase two fold
(d) decrease twice

Question. Weight of 1 L milk is 1.032 kg. It contains butter fat (density 865 kgm ⁻³) to the extent of 4% by volume/volume. The density of the fat free skimmed milk will be
(a) 1038.5 kgm ⁻³
(b) 1032.2 kgm ⁻³
(c) 997 kgm ⁻³
(d) 1000.5 kgm ⁻³

Question. A 0.2075 g sample of an oxide of cobalt on analysis was found to contain 0.1475 g cobalt. The empirical formula of the oxide is
(a) CoO2
(b) Co O 2 3
(c) CoO
(d) Co O 4 6

Question. The weight of11 × 10²² molecules of CuSO₄ 5H₂O is
(a) 41.59 g
(b) 415.9 g
(c) 4.159 g
(d) None of these

Question. The number of moles of (NH₄ )₂SO₄ Fe₂ (SO₄)₃ 24H₂O formed from a sample containing 0.0056 g of Fe is
(a) 10 ⁻⁴ mol
(b) 0.5 ×10⁻⁴ mol
(c) 2 10 × ⁻⁴ mol
(d) 0.33× 10⁻⁴ mol

Question. A student performs a titration with different burettes and finds titre values of 25.2 mL, 25.25 mL and 25.0 mL. The number of significant figures in the average titre value is 
(a) 1
(b) 2
(c) 3
(d) 4

Question. A metal oxide contains 53% metal and carbon dioxide contains 27% carbon. Assuming the law of reciprocal proportions, the percentage of metal in the metal carbide is
(a) 75%
(b) 25%
(c) 37%
(d) 66%

Question. A gaseous hydrocarbon gives upon combustion 0.72 g of water and 3.08 g of CO₂. The empirical formula of the hydrocarbon is 
(a) C₂ H₄
(b) C₃ H₄
(c) C₆ H ₅
(d) C₇ H₈

Question. A mixture contains Na₂ C₂ O₄ and KHC₂O₄ in1:1molar ratio. Mixture is neutralised by 100 mL of 0.01 M KOH. What volume of 0.01 M KMnO₄? Thus, the same mixture is oxidised by
(a) 200 mL
(b) 100 mL
(c) 90 mL
(d) 80 mL

Question. At 300 K and 1 atom, 15 mL of a gaseous hydrocarbon requires 375 mL air containing 20%O₂ by volume for complete combustion. After combustion, the gases occupy 330 mL. Assuming that the water, formed is in liquid form and the volumes were measured at the same temperature and pressure, the formula of the hydrocarbon is 
(a) C₃ H₈ 
(b) C₄ H₈
(c) C₄ H ₁₀
(d) C₃ H₆

Question. 1 mole of potassium chlorate is thermally decomposed and excess of aluminium is burnt in the gaseous product. How many moles of aluminium oxide are formed?
(a) 1
(b) 2
(c) 1.5
(d) 3

Question. Amount of A FeSO₄ (NH₄ )₂ SO₄ 6H₂ (molar mass 392gmol= ^–1) must be dissolved and diluted to 250 mL to prepare an aqueous solution of density1.00 g mL ⁻¹, i.e. 1.00 ppm Fe²⁺ by weight is
(a) 3.50 × 10⁻³ g 
(b) 1.75 × 10⁻³ g 
(c) 7.00 × 10⁻³ g 
(d) 0.35 × 10⁻³ g 

Question. The ratio of mass per cent of C and H of an organic compound (C_x H_y O_z ) is 6 : 1. If one molecule of the above compound (C_x H_y O_z ) contains half as much oxygen as required to burn one molecule of compound C_x H_y completely to CO₂ andH O₂ . The empirical formula of compound C_x H_y O_z is 
(a) C₃ H₆ O₃
(b) C₄ H₈
(c) C₃ H₄ O₂
(d) C₂ H₄ O₃

Question. A mixture of FeO and Fe₃O₄ when heated in air to constant weight, gains 5% in its weight. What is the percentage of Fe₃O₄ in mixture?
(a) 73.87%
(b) 26.13%
(c) 79.75%
(d) 20.25%

Question. If 0.5 mole of BaCl₂ are mixed with 0.2 mole 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

Question. The reaction between yttrium metal and dil. HCl produces H₂S and y³⁺ ions. The molar ratio of yttrium to that hydrogen produced is
(a) 1:2
(b) 2:1
(c) 2:3
(d) 5:2

Question. If 10²¹ molecules are removed from 200 mg of CO₂, the number of moles of CO₂ left are
(a) 2.88 × 10 ⁻³
(b) 28.8 × 10 ⁻³
(c) 0.288 × 10 ⁻³
(d) 1.66 × 10 ⁻²

Question. Medical experts generally consider a lead level of 30 μg Pb per dL of blood to pose a significant health risk ( 1 dL = 0.1 L). Express this lead level as the number of Pb atoms per cm³ blood (Pb = 207).
(a) 8.72 × 10¹⁴
(b) 8.72 × 10¹⁵
(c) 8.72 × 10 ¹³
(d) 8.72 × 10 ¹⁶

Question. The correctly reported answer of the addition of 4.523, 2.3 and 6.24 will have significant figures
(a) two
(b) three
(c) four
(d) five

Question. 3 g of activated charcoal was added to 50 mL of acetic acid solution (0.06 N) in a flask. After an hour it was filtered and the strength of the filtrate was found to be 0.042 N. The amount of acetic acid adsorbed (per gram of charcoal) is 
(a) 18 mg
(b) 36 mg
(c) 42 mg
(d) 54 mg

Question. 5 mL of N HCl, 20 mL of N/2 H₂ SO₄ and 30 mL of N/3 HNO₃ are mixed together and volume made to 1 L. The normality of resulting solution is
(a) 0.45
(b) 0.025
(c) 0.9
(d) 0.05

Question. What volume of hydrogen gas at 273 K and 1 atm pressure will be consumed in obtaining 21.6 g of elemental boron (atomic mass = 10.8) from the reduction of boron trichloride by hydrogen ?
(a) 89.6 L
(b) 67.2 L
(c) 44.8 L
(d) 22.4 L

Question. 1.00 × 10⁻³ moles of Ag⁺ and 1.00 10 × ⁻³ moles of CrO₄²⁻ react together to form solid Ag₂CrO₄.Calculate the amount of Ag₂CrO₄ formed (Ag₂CrO₄  = 331.73 g mol⁻¹ ) .
(a) 0.268 g
(b) 0.166 g
(c) 0.212 g
(d) 1.66 g

Question. Two solutions of a substance (non-electrolyte) are mixed in the following manner : 480 mL of 1.5 M of first solution with 520 mL of 1.2 M of second solution. The molarity of final solution is
(a) 1.20 M
(b) 1.50 M
(c) 1.344 M
(d) 2.70 M 

Question. The reaction,N₂ + 3H₂ →2NH₃ is used to produce ammonia. When 450 g of hydrogen was reacted with nitrogen, 1575 g of ammonia were produced. What is the per cent yield of this reaction?
(a) 61.8%
(b) 41.5%
(c) 30.8%
(d) 20.7%

Question. Sea water contains 65 × 10 ⁻³ g L ⁻¹ of bromide ions. If all the bromide ions are converted to produce Br₂, how much sea water is needed to prepare 1 kg Br₂ ?
(a) 15.38 L
(b) 15.38 × 10³ L 
(c) 7.69 × 10³ L 
(d) 76.9 L

Question. 0.376 g of Al reacted with an acid to displace 0.468 L of H₂ measured in standard conditions. Equivalent volume of H₂ formed is (equivalent mass of Al is 9 g equiv⁻¹)
(a) 22.4 L
(b) 5.6 L
(c) 11.2 L
(d) 2.24 L

Question. The same amount of a metal combines with 0.200 g of oxygen and with 3.17 g of a halogen. Hence, equivalent mass of halogen is
(a) 127 g
(b) 80 g
(c) 35.5 g
(d) 9 g

Question. A sample of ammonium phosphate, (NH₄)₃ PO₄ contains 3.18 moles of hydrogen atoms. The number of moles of oxygen atoms in the sample is
(a) 0.265
(b) 0.795
(c) 1.06
(d) 3.18

Question. Excess of carbon dioxide is passed through 50 mL of 0.5 m calcium hydroxide solution. After completion of the reaction, the solution was evaporated to dryness. The solid calcium carbonate was completely neutralised with 0.1 N hydrochloric acid. The volume of hydrochloric acid required is (atomic mass of calcium = 40).
(a) 300 cm3
(b) 200 cm3
(c) 500 cm3
(d) 400 cm3

Question. Sodium nitrate on reduction with Zn in the presence of NaOH solution producesNH₃. Mass of sodium nitrate absorbing 1 mole of electron will be
(a) 7.750
(b) 10.625
(c) 8.000
(d) 9.875

Question. Haemoglobin contains 0.33% of iron by weight. The molecular weight of haemoglobin is approximately 67200. The number of iron atoms (at. wt. of Fe is 56) present in one molecule of haemoglobin are
(a) 1
(b) 6
(c) 4
(d) 2

Question. How much AgCl will be formed by adding 200 mL of 5 N HCl to a solution containing 1.7 g AgNO₃ (Ag =108)?
(a) 0.1435 g
(b) 1.435 g
(c) 14.35 g
(d) 143.5 g

Question. Density of 2.05 M solution of acetic acid in water is 1.02 g/mL. The molality of same solution is
(a) 1.14 mol kg⁻¹
(b) 3.28 mol kg⁻¹
(c) 2.28 mol kg⁻¹
(d) 0.44 mol kg⁻¹

Question. 1 mole of N₂ and 4 moles of H₂ are allowed to react in a vessel and after reaction,H O₂ is added. Aqueous solution required 1 mole of HCl. Mole fraction ofH₂ in the gaseous mixture after reaction is
(a) 1/6
(b) 5/6
(c) 1/3
(d) None of these

Question. The molecular formula of a commercial resin used for exchanging ions in water softening is C₈H₇SO₃Na (Mol. wt. = 206). What would be the maximum uptake of Ca²⁺ ions by the resin when expressed in mole per gram resin? 
(a) 1/103
(b) 1/206
(c) 2/309
(d) 1/412

Question. A 15.00 mL sample of a solution is 0.04 M in Sn²⁺ and x M in Fe²⁺ . Both are easily oxidised by Cr₂O^2–₇ in acidic solution to Sn⁴⁺ and Fe³⁺ and itself reduced to Cr . ³⁺ 18.0 mL of 0.125 M Cr₂O^2–₇ is required. Thus, x is
(a) 0.410
(b) 0.205
(c) 0.820
(d) 1.640

Question. Acidified KMnO₄ oxidises oxalic acid to CO₂.What is the volume (in litres) of10⁻⁴MKMnO₄ required to completely oxidise 0.5 L of10⁻² M oxalic acid in acidic medium?
(a) 125
(b) 1250
(c) 200
(d) 20

Question. The number of H-atoms present in 25.6 g of sucrose which has a molar mass of 342.3 g is
(a) 22 × 10₂₃
(b) 9.91 × 10₂₃
(c) 11 × 10₂₃
(d) 44 × 10₂₃

Question. The most abundant elements by mass in the body of a healthy human adult are oxygen (61.4%), carbon (22.9%), hydrogen (10.0%) and nitrogen (2.6%). The weight which a 75 kg person would gain if allH atoms are replaced by² H atoms is
(a) 15 kg
(b) 37.5 kg
(c) 7.5 kg
(d) 10 kg

We hope the above multiple choice questions for Class 11 Chemistry for Chapter 1 Some Basic Concepts of Chemistry provided above with answers based on the latest syllabus and examination guidelines issued by CBSE, NCERT and KVS are really useful for you. Some Basic Concepts of Chemistry is an important chapter in Class 11 as it provides very strong understanding about this topic. Students should go through the answers provided for the MCQs after they have themselves solved the questions. All MCQs have been provided with four options for the students to solve. These questions are really useful for benefit of class 11 students. Please go through these and let us know if you have any feedback in the comments section.