The number of oxygen atoms in $4.4 \ g$ of $CO_2$ is approximately ........ $\times 10^{23}$.

What is the weight of $3.01 \times 10^{23}$ molecules of ammonia in grams?

In which case is the number of molecules of water maximum?

Among the following,choose the ones with an equal number of atoms.
$A$. $212 \ g$ of $Na_2CO_3(s)$ [molar mass $= 106 \ g/mol$]
$B$. $248 \ g$ of $Na_2O(s)$ [molar mass $= 62 \ g/mol$]
$C$. $240 \ g$ of $NaOH(s)$ [molar mass $= 40 \ g/mol$]
$D$. $12 \ g$ of $H_2(g)$ [molar mass $= 2 \ g/mol$]
$E$. $220 \ g$ of $CO_2(g)$ [molar mass $= 44 \ g/mol$]
Choose the correct answer from the options given below.

$7.0 \, g$ of $N_2$,$8.0 \, g$ of $O_2$,and $34.0 \, g$ of $NH_3$ are present in a $1 \, L$ vessel. The active masses in $mol \, L^{-1}$ are respectively:

What is the mass of $1 \times 10^{22}$ molecules of $CuSO_4 \cdot 5H_2O$?