19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
1.520 g of hydroxide of a metal on ignition gave 0.995 g of oxide. The equivalent weight of metal is (JCECE 2008)
Assertion : 1mole of H2SO4 is neutralised by 2 moles of NaOH but 1 equivalent of H2SO4 is neutralised by 1 equivalent of NaOH. Reason : Equivalent weight of H2SO4 is half of its molecular weight while e…
Assertion :For a binary solution of two liquids, A and B, with the knowledge of density of solution, molarity can be converted into molality. Reason: Molarity is defined in terms of volume and molality …
A mixture of CaCl2 and NaCl weighing 4.44 g is treated with sodium carbonate to precipitate all the Ca2+ ions as calcium carbonate. The calcium carbonate so obtained is heated strongly to get 0.56 g of CaO. The percen…
Volume of a gas at NTP is 1.12×10–7 cm3. The number of molecules in it is (Manipal 2010)
If 1 mL of water contains 20 drops the number of molecules in a drop of water is (AFMC 2010)
74.5 g of a metallic chloride contain 35.5 g of chlorine. The equivalent weight of the metal is (Manipal 2010)
To dissolve 0.9 g metal, 100 mL of 1N HCl is used. What is the equivalent weight of metal? (MP PMT 2010)
In an experiment, 4 g of M2Ox oxide was reduced to 2.8 g of the metal. If the atomic mass of the metal is 56 g mol–1, the number of O atoms in the oxide is (AFMC 2010)
10 g of hydrogen and 64 g of oxygen were filled in a steel vessel and exploded. Amount of water produced in this reaction will be (AIPMT 2009)
The volume of 2 N H2SO4 solution is 0.1 dm3. The volume of its decinormal solution (in dm3) will be (MHT CET 2009)
20.0 g of a magnesium carbonate sample decomposes on heating to give carbon dioxide and 8.0g magnesium oxide. What will be the percentage purity of magnesium carbonate in the sample ? (NEET 2015)
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)
If Avogadro number NA, is changed from 6.022 × 1023 mol–1 to 6.022 × 1020 mol–1, this would change (NEET 2015)
The number of water molecules is maximum in (NEET 2015)
What is the mass of the precipitate formed when 50 mL of 16.9% solution of AgNO3 is mixed with 50 mL of 5.8% NaCl solution? (Ag = 107.8, N = 14, O = 16, Na = 23, Cl = 35.5) (NEET 2015)
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)