Molar mass is the ratio of the mass to that amount of the substance. The mass of the barium nitrate in the formula unit is 23.0 grams.
The mass of a substance is the product of the molar mass of the compound and the number of moles of the compound.
Given,
Molar mass of barium nitrate = 261.35 g/mol
If, [tex]6.022 \times 10^{23}[/tex] have a mass of 261.35 g/mol then, [tex]5.30 \times 10^{22}[/tex] formula units will have a mass of,
[tex]\begin{aligned}& = \dfrac{261.35 \times 5.30 \times 10^{22}}{6.022\times 10^{23}}\\\\&= 23.0\;\rm gm\end{aligned}[/tex]
Therefore, option C. 23.0 gm is the mass of barium nitrate.
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