How many moles of helium gas occupy $22.4 \ L$ at $0^o C$ and $1 \ atm$ pressure?

Assertion : The number of $O$ atoms in $16 \ g$ of oxygen and $16 \ g$ of ozone is same.
Reason : Each of the species represents $1 \ g$ molecule of oxygen.

$A$ $500 \, mL$ solution of $NaOH$ contains $3.01 \times 10^{22}$ molecules of $NaOH$. What is the molarity $(M)$ of the $NaOH$ solution?

How many moles of $Mg_{3}(PO_{4})_{2}$ contain $0.25$ moles of $O$ atoms?

The mass of $0.1 \ mol$ of methane $(CH_4)$ is ...... $g$.

Find the total number of electrons,protons,and neutrons in $0.192 \ g$ of $_{16}^{32}S$.