19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Which of the following contains atoms equal to those in 12 g Mg ? (At. wt. Mg = 24)
Which of the following statements(s) is false about the arrangement of particles, in different states of matter?
Which of the following represents 180 g of water correctly? (I) 5 moles of water. (II) 10 moles of water. (III) 6.023 × 1023 molecules of water. (IV) 6.023 × 1024 molecules of water. Choose the correct option.
The mass of 112 cm3 of CH4 gas at STP is
The number of molecules in 89.6 litre of a gas at NTP are :
The mass of one mole of a substance in grams is called its …A… Here, A refers to
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?
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‘amu’ has been replaced by ‘u’ which is known as …A… Here, A refers to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…
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
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
Who proposed 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?
One of the statements of Dalton’s atomic theory in given below “Compounds are formed when atoms of different elements combine in a fixed ratio” Which of the following laws is not related to this…
In 1811, Avogadro proposed that equal volumes of gases at the same …A… and …B… should contain equal number of molecules. Here, A and B refer to
The Gay Lussac’s law was explained properly by the work of …A… in 1811. Here, A refers to