A 20 L vessel contains 0.1 mole of $O_2$ at 300 K. $O_3$ is prepared in the vessel by subjecting $O_2$ to silent electric discharge till the volume is reduced to 15 L at 300K. What is the number of moles of $O_3$ formed?

Oxidation number of carbon in carbon suboxide is :

How many water molecules are present in 36 grams of water?

Number of molecules in 1 ml of ${O_2}$ at NTP

A mixture of $CO_2$ and $N_2$ gases contains 0.44 g of $CO_2$ and 0.56 g of $N_2$. The total number of moles of gases in the mixture is:

Suppose the elements X and Y combine to form two compounds $X{Y_2}$ and ${X_3}{Y_2}$. When 0.1 mole of $X{Y_2}$ weights 10 g and 0.05 mole of ${X_3}{Y_2}$ weights 9 g, the atomic weights of X and Y are

Suppose the Avogadro constant was $6.022 imes 10^{18} \, mol^{-1}$. How many atoms would be present in 0.5 moles of helium?

Which of the following has greatest no. of atoms

A gaseous mixture contains oxygen and nitrogen in the ratio of $1:4$ by weight. Therefore, the ratio of their number of molecules is:

The mass of 2.5 g.atom of oxygen is

0.3 g of an oxalate salt was dissolved in 100 mL solution. The solution required 90 mL of $N/20$ ${\rm{KMn}}{{\rm{O}}_4}$ for complete oxidation. The % of oxalate ion in salt is: