19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Number of molecules in 1 litre of oxygen at STP is : (a) 6.02×10 (b) 6.02×10 22.4
M g of a substance when vaporised occupy a volume of 5.6 litre at NTP. The molecular mass of the substance will be :
The weight of one molecule of the compound C₆₀H₁₂₂ is
The number of molecules in 4.25 g of ammonia is about
How many H₂O molecules are in a 0.10g sample of CuSO₄.5H₂O (M = 249.7) ?
A gaseous mixture contains oxygen and nitrogen in the ratio of 1 : 4 by weight. Therefore, the ratio of their number of molecules is
How many moles of magnesium phosphate, Mg₃ (PO₄)₂ will contain 0.25 mole of oxygen atoms ?
Which of the following gases will have the least volume if 10 g of each gas is taken at same temperature and pressure?
Given that the abundances of isotopes 54Fe, 56Fe and 57Fe are 5%, 90% and 5%, respectively, the atomic mass of Fe is
Calculate the molecular mass of sucrose (C₁₂H₂₂O₁₁) molecule?
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…
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 :
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:
Carbon and oxygen combine to form two oxides, carbon monoxide and carbon dioxide in which the ratio of the weights of carbon and oxygen is respectively 12:16 an 12:32. These figures illustrate the:
Which of the following reaction is not according to the law of conservation of mass
If 6.3g of NaHCO₃ are added 15.0g CH₃COOH solution, the residue is found to weigh 18.0 g. What is the mass of CO₂ released in the reaction?
Which law states that if two elements can combine to form more than one compound, the masses of one element that combine with a fixed mass of other element, are in the ratio of small whole number?
…A… are formed when atoms of different elements combine in a …B… ratio. Here, A and B refer to
Which of the following has the largest volume ?
Statement I: The temperatures in degree Celsius and degree Fahrenheit are related to each other by the following relationship. º F º C Statement II The temperature on degree Celsius and Kelvin sc…
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
In one molal solution that contains 0.5 mole of a solute, there is (NEET 2022)