19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Which of the given reactions are counted as balanced reactions? (a) H +O 2H O → (b) 4Al+3O 2Al O → (c) Mg OH +2HNO 2Mg NO +2H O → (d) N +3H NH → Ans. (b) Sol. Al O Al O → is a balanced reaction because the number of a…
According to the law of conservation of mass …A… has the same number of atoms of each element on both sides of the equation. Here, A refers to
If two compounds have the same empirical formula but different molecular formula, they must have
What is the percentage of carbon, in ethanol?
The ratio of masses of oxygen and nitrogen in a particular gaseous mixture is 1: 4. The ratio of number of their molecule is :
The number of moles of SO₂Cl₂ in 13.5 g is :
Choose the wrong statement:
What’s the number of particles in 10 moles of hydrochloric acid? a) 6.022 × 1024 particles b) 6.022 × 1023 particles c) 6.22 × 1023 particles d) 3.22 × 1022 particles
If one mole of ammonia contains “y” number of particles, then how many particles do 1 mole of glucose contain?
According to S.I. system, ______ was used to measure the amount of substance.
The mass of one mole of a substance in grams is called its …A… Here, A refers to
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‘amu’ has been replaced by ‘u’ which is known as …A… Here, A refers to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 …
The law of conservation of mass holds good for all of the following except:
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:
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
Who proposed Law of Conservation of Mass?
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