19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Number of atoms of He in 100 u of He (atomic weight of He is 4) are (BCECE 2008)
The maximum number of molecules are present in (BCECE 2008)
Mass of 0.1 mole of methane is (KCET 2008)
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 closest to (AIPMT 2007)
The crystalline salt Na₂SO₄.xH₂O on heating loses 55.9% of its weight. The formula of crystalline salt is (Kerala CEE 2007)
Gram molecular volume of oxygen at STP is (KCET 2007)
The number of gram molecules of chlorine in 6.02×1025 hydrogen chloride molecule is (KCET 2007)
25 g of MCl₄ contains 0.5 mole chlorine then its molecular weight is (Punjab PMET 2007)
The weight of one molecule of a compound C₆₀H₁₂₂ is (BHU 2007)
Which of the following 1 g L–1 solution has the highest normality ?
10 mL of 0.2 N HCl and 30 mL of 0.1 N HCl together exactly neutralises 40 mL of solution of NaOH, which is also exactly neutralised by a solution in water of 0.61 g of an organic acid.What is…
The vapour density of a chloride of an element is 39.5. The Ew of the elements is 3.82. The atomic weight of the element is
2H₃PO₄ + 3 Ca(OH)₂Ca₃(PO₄)₂ + 6 H₂O Equivalent weight of H₃PO₄ in this reaction is
The normality of 0.3 M phosphorous acid (H₃PO₃) is
50 ml of 10 N H₂SO₄, 25 ml of 12 N HCl and 40 ml of 5N HNO₃ were mixed together and the volume of the mixture was made 1000 ml by adding water. The normality of the resulting solution will be
10 mL of N/2 HCl, 20 mL of N/2 H₂SO₄ and 30 mL N/3 HNO₃are mixed together and solution made to one litre. The normality of the resulting solution is
To neutralize completely 20 mL of 0.1 M aqueous solution of phosphorus (H₃PO₃) acid, the volume of 0.1 M aqueous KOH solution required is
6.023 × 1020 molecules of urea are present in 100 mL of its solution. The concentration of urea solution is
25 mL of a solution of Ba(OH)₂ on titration with a 0.1 M solution of HCl gave a titre value of 35 mL. The molarity of barium hydroxide solution was
Assertion :When a solution is diluted from volume V₁ to V₂ by adding solvents, its molarity before dilution M1 and after dilution M2 are related as : M1V₁ = M2V₂ Reason:During dilution, moles of the solute remains co…
A standard solution of 0.165 M HCl is being used to determine the concentration of an unknown NaOH solution. If 25.5 mL of an acid solution are required to neutralize 15.0 mL of the base, what is the mo…
Molarity equation of a mixture of solutions of same substance is given by (a) M V M V M V ... M M M x x x x (b) M V M V M V ... M V V V (c) M M M ... M V V V V V V (d) M M M ... M V V V V V V x x Ans. (b) Sol. Molarit…
The density of a solution prepared by dissolving 120g of urea (mol. mass = 60 u) in 1000 g of water is 1.15g/mL. The molarity of this solution is
Mole fraction of ethanol in ethanol - water mixture is 0.25. Hence, percentage concentration of ethanol (C₂H₆O) by weight of mixture is
What is the weight % sulphuric acid in an aqueous solution which is 0.502 M in sulphuric acid? The specify gravity of the solution is 1.07