19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
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…
The number of atoms in 0.1 mol of a triatomic gas is ( A N =6.022×10 ) (CBSE AIPMT 2010)
60g of a compound on analysis produced 24g of carbon, 4g hydrogen and 32g oxygen. The empirical formula of the compound is. (BVP 2010)
20.0 kg of N2(g) and 3.0 kg of H2(g) are mixed to produce NH3 (g). The amount of NH3(g) formed is (Kerala CEE 2011)
The vapour density of a gas is 11.2. The volume occupied by one gram of the gas at STP is (Manipal – 2013)
6.02 × 1020 molecules of urea are present in 100 mL of its solution. The concentration of solution is (NEET 2013)
Equal masses of H2, O2 and methane have been taken in a container of volume V at temperature 27°C in identical conditions. The ratio of the volumes of gases H2 : O2 : methane would be (NEET 2014)
When 22.4 litres of H2(g) is mixed with 11.2 litres of Cl2(g), each at STP, the moles of HCl(g) formed is equal to (NEET 2014)
Calculate the molecular mass of sucrose (C12H22O11) molecule?
What is the mass of hydrogen in terms of amu?
What’s the formula mass of NaCl?
‘amu’ has been replaced by ‘u’ which is known as …A… Here, A refers to
Statement I: The constituents of a compound can be separated into simpler substances by physical method. Statement II: The constituents of compound can be separated by chemical method. Choose the correct …
Consider the following statements, (I) Mixture may contain the components in any ratio and their composition is variable. (II) Pure substances have fixed composition. (III) The constituents of pure substanc…
Assertion :Pure water obtained from different states of India always contains hydrogen and oxygen in the ratio of 1 : 8 by mass. Reason: Total mass of reactants and products during chemical change is always the …
A sample of calcium carbonate (CaCO3) has the following percentage composition: Ca = 40%, C = 12%, O = 48%. If the law of constant proportions is true, then the weight of calcium in 4g of a s…
The law of conservation of mass holds good for all of the following except:
3 g of a hydrocarbon on combustion in excess of oxygen produces 8.8g of CO2 and 5.4 g of H2O. The data illustrates the law of:
Zinc sulphate contains 22.65% Zn and 43.9% H2O. If the law of constant proportions is true, then the mass of zinc required to give 40g crystals will be :
If water sample are taken from sea, rivers or lake, they will be found to contain hydrogen and oxygen in the approximate ratio of 1:8. This indicates the law of:
A sample of CaCO3 has Ca = 40%, C = 12% and O = 48%. If the law of constant proportions is true, then the mass of Ca in 5 g of CaCO3 from another source will be :
n g of substance X reacts with m g of substance Y to form p g of substance R and q g of substance S. This reaction can be represented as follows : X + Y = R + S The relation which can be established in the amounts of…
Hydrogen and oxygen combine to form H2O2 and H2O containing 5.93% and 11.2% hydrogen respectively. The data illustrates:
The percentage of copper and oxygen in samples of CuO obtained by different methods were found to be the same. This illustrates the law of
The law of multiple proportion is illustrated by