19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
The number of molecules in 18 mg of water in terms of Avogadro number NA is (J&K CET 2009)
One atom of an element weighs 1.8 × 10–22 g. Its atomic mass is (Manipal 2009)
A gas mixture contains O₂ and N₂ in ratio of 1:4 by weight. The ratio of their number of molecules is (JIPMER 2008)
1.520 g of hydroxide of a metal on ignition gave 0.995 g of oxide. The equivalent weight of metal is (JCECE 2008)
A metal M of equivalent mass E forms an oxide of molecular formula MxOy. The atomic mass of the metals is given by the correct equation (BCECE 2008)
The equivalent weight of a metal is 9 and vapour density of its chloride is 59.25. The atomic weight of metal is (DUMET 2008)
Of two oxides of iron, the first contained 22% and the second contained 30% of oxygen by weight. The ratio of weights of iron in the two oxides that combine with the same weight of oxygen is (J&K CET 2008)
How many moles of lead (II) chloride will be formed from a reaction between 6.5 g of PbO and 3.2 g of HCl? (CBSE AIPMT 2008)
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
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