19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Which has maximum number of atoms?
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 water molecules present in a drop of water (volume = 0.0018 ml) at room temperature is (density of H2O = 1 g/mL)
The largest number of molecules is in
Rearrange the following I to IV in order of increasing masses and choose the correct answer [At. wt. of N = 14 u, O = 16 u, Cu = 63 u] I 1 molecule of oxygen II 1 atom of nitrogen III 1 × 10–10mol molecule of oxygen…
Which among the following is the heaviest?
If NA is Avogadro’s number then number of valence electrons in 4.2 g of nitride ions (N3–) is
Which of the following weighs the least ?
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 ?
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.
Which of the following gases will have the least volume if 10 g of each gas is taken at same temperature and pressure?
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?
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
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)
6.02 × 1020 molecules of urea are present in 100 mL of its solution. The concentration of solution is (NEET 2013)