JEE (Some Basic concept of chemistry)

Q1: 5 moles of AB2 weight 125 × 10^3 kg and 10 moles of A2B2 weight 300 × 10^-3 kg. The molar mass of A(MA) and molar mass of B (MB) in kg mol⁻¹ are (2019 Main, 12 April I)

• MA = 10 × 10^-3 and MB = 5 × 10^-3
• MA = 50 × 10^-3 and MB = 25 × 10^-3
• MA = 25 × 10^-3 and MB = 50 × 10^-3
• MA = 5 × 10^-3 and MB = 10 × 10^-3

Q2: The minimum amount of O2(g) consumed per gram of reactant is for the reaction (Given atomic mass: Fe = 56, O = 16, Mg = 24, P = 31, C = 12, H = 1) (2019 Main, 10 April II)

• C3H8(g) + 5O2(g) → 3CO2(g) + 4H2O(l)
• P4(s) + 5O2(g) → P4O10(s)
• 4Fe(s) + 3O2(g) → 2Fe2O3(s)
• 2Mg(s) + O2(g) → 2MgO(s)

Q3: At 300 K and 1 atmospheric pressure, 10 mL of a hydrocarbon required 55 mL of O2 for complete combustion and 40 mL of CO2 is formed. The formula of the hydrocarbon is (2019 Main, 10 April I)

• C4H7Cl
• C4H6
• C4H10
• C4H8

Q4: 10 mL of 1 mM surfactant solution forms a monolayer covering 0.24 cm² on a polar substrate. If the polar head is approximated as a cube, what is its edge length? (2019 Main, 9 April II)

• 2.0 pm
• 0.1 nm
• 1.0 pm
• 2.0 nm

Q5: For a reaction, N2(g) + 3H2(g) → 2NH3(g), identify dihydrogen (H2) as a limiting reagent in the following reaction mixtures. (2019 Main, 9 April I)

• 56 g of N2, 10 g of H2
• 35 g of N2, 8 g of H2
• 14 g of N2, 4 g of H2
• 28 g of N2, 6 g of H2

Q6: The percentage composition of carbon by mole in methane is (2019 Main, 8 April II)

• 75%
• 20%
• 25%
• 80%

Q7: 8 g NaOH is dissolved in 18 g of H2O. Mole fraction of NaOH in solution and molality (in mol kg⁻¹) of the solution respectively are (2019 Main, 12 Jan II)

• 0.2, 11.11
• 0.167, 22.20
• 0.2, 22.20
• 0.167, 11.11

Q8: The volume strength of 1 M H2O2 is (Molar mass of H2O2 = 34 g mol⁻¹) (2019 Main, 12 Jan II)

• 16.8
• 22.4
• 11.35
• 5.6

Q9: The amount of sugar (C12H22O11) required to prepare 2 L of its 0.1 M aqueous solution is (2019 Main, 10 Jan II)

• 17.1 g
• 68.4 g
• 136.8 g
• 34.2 g

Q10: For the following reaction, the mass of water produced from 445 g of C57H110O6 is: 2C57H110O6(s) + 163O2(g) → 114CO2(g) + 110 H2O (l) (2019 Main, 9 Jan II)

• 490 g
• 495 g
• 445 g
• 890 g

Q11: A solution of sodium sulphate contains 92 g of Na⁺ ions per kilogram of water. The molality of Na⁺ ions in that solution in mol kg⁻¹ is (2019 Main, 9 Jan I)

• 16
• 4
• 132
• 8

Q12: 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 all ¹H atoms are replaced by ²H atoms is (2017 JEE Main)

• 15 kg
• 37.5 kg
• 7.5 kg
• 10 kg

Q13: 1 g of a carbonate (M2CO3) on treatment with excess HCl produces 0.01186 mole of CO2. The molar mass of M2CO3 in g mol⁻¹ is (2017 JEE Main)

• 1186
• 84.3
• 118.6
• 11.86

Q14: At 300 K and 1 atm, 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 (2016 JEE Main)

• C3H8
• C4H8
• C4H10
• C3H6

Q15: The molecular formula of a commercial resin used for exchanging ions in water softening is C8H7SO3Na (molecular weight = 206). What would be the maximum uptake of Ca²⁺ ions by the resin when expressed in mole per gram resin? (2015 JEE Main)

• 1/103
• 1/206
• 2/309
• 1/412

Q16: 3 g of activated charcoal was added to 50 mL of acetic acid solution (0.06N) 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 (2015 JEE Main)

• 18 mg
• 36 mg
• 42 mg
• 54 mg

Q17: The ratio mass of oxygen and nitrogen of a particular gaseous mixture is 1: 4. The ratio of number of their molecules is (2014 Main)

• 1:4
• 7:32
• 1:8
• 3:16

Q18: The molarity of a solution obtained by mixing 750 mL of 0.5 M HCl with 250 mL of 2 M HCl will be (2013 Main)

• 0.875 M
• 1.00 M
• 1.75 M
• 1.05 M

Q19: Dissolving 120 g of urea (mol. wt. 60) in 1000 g of water gave a solution of density 1.15 g/mL. The molarity of the solution is (2011)

• 1.78 M
• 2.00 M
• 2.05 M
• 2.22 M

Q20: Given that the abundances of isotopes ⁵⁴Fe, ⁵⁶Fe and ⁵⁷Fe are 5%, 90% and 5%, respectively, the atomic mass of Fe is (2009)

• 55.85
• 55.95
• 55.75
• 56.05

Q21: Mixture X: 0.02 mole of [Co(NH3)5SO4]Br and 0.02 mole of [Co(NH3)5Br]SO4 was prepared in 2 L solution. 1 L of mixture X + excess of AgNO3 solution → Y 1 L of mixture X + excess of BaCl2 solution → Z Number of moles of Y and Z are (2003, 1M)

• 0.01, 0.01
• 0.02, 0.01
• 0.01, 0.02
• 0.02, 0.02

Q22: Which has maximum number of atoms? (2003, 1M)

• 24 g of C (12)
• 56 g of Fe (56)
• 27 g of Al (27)
• 108 g of Ag (108)

Q23: How many moles of electron weighs 1 kg? (2002, 3M)

• 6.023 × 10^23
• 1 / (9.108 × 10^31)
• 6.023 × 10^54 / 9.108
• 1 / (9.108 × 6.023 × 10^8)

Q24: The normality of 0.3 M phosphorus acid (H3PO3) is (1999, 2M)

• 0.1
• 0.9
• 0.3
• 0.6

Q25: In which mode of expression, the concentration of a solution remains independent of temperature? (1988, 1M)

• Molarity
• Normality
• Formality
• Molality

Q26: A molal solution is one that contains one mole of solute in (1986, 1M)

• 1000 g of solvent
• 1.0 L of solvent
• 1.0 L of solution
• 22.4 L of solution

Q27: If 0.50 mole of BaCl2 is mixed with 0.20 mole of Na3PO4, the maximum number of moles of Ba3(PO4)2 that can be formed is (1981, 1M)

• 0.70
• 0.50
• 0.20
• 0.10

Q28: 2.76 g of silver carbonate on being strongly heated yields a residue weighing (1979, 1M)

• 2.16 g
• 2.48 g
• 2.32 g
• 2.64 g

Q29: When the same amount of zinc is treated separately with excess of sulphuric acid and excess of sodium hydroxide, the ratio of volumes of hydrogen evolved is (1979, 1M)

• 1:1
• 1:2
• 2:1
• 9:4

Q30: The largest number of molecules is in (1979, 1M)

• 36 g of water
• 28 g of CO
• 46 g of ethyl alcohol
• 54 g of nitrogen pentaoxide (N2O5)

Q31: The total number of electrons in one molecule of carbon dioxide is (1979, 1M)

• 22
• 44
• 66
• 88

Q32: A gaseous mixture contains oxygen and nitrogen in the ratio of 1:4 by weight. Therefore, the ratio of their number of molecules is (1979, 1M)

• 1:4
• 1:8
• 7:32
• 3:16

Q33: Galena (an ore) is partially oxidised by passing air through it at high temperature. After some time, the passage of air is stopped, but the heating is continued in a closed furnace such that the content undergo self-reduction. The weight (in kg) of Pb produced per kg of O2 consumed is ________. (Atomic weights in g mol⁻¹ : O = 16, S = 32, Pb = 207) (2018 Adv.)

Q34: To measure the quantity of MnCl2 dissolved in an aqueous solution, it was completely converted to KMnO4 using the reaction, MnCl2 + K2S2O8 + H2O → KMnO4 + H2SO4 + HCl (equation not balanced). Few drops of concentrated HCl were added to this solution and gently warmed. Further, oxalic acid (225 mg) was added in portions till the colour of the permanganate ion disappeared. The quantity of MnCl2 (in mg) present in the initial solution is ________. (Atomic weights in g mol⁻¹: Mn = 55, Cl = 35.5) (2018 Adv.)