A crystalline sample has a mass of and is composed purely of (molar mass )

CHEMISTRY · Single correct · A Level · Chemistry · Amount of substance · Amount of substance

Problem

A crystalline sample has a mass of

6.50\,\text{g}

and is composed purely of

\mathrm{NaCl}

(molar mass

58.44\,\text{g\,mol}^{-1}

). Approximately how many formula units of

\mathrm{NaCl}

are in the sample? (a)

1.10\times10^{23}

formula units (b)

1.03\times10^{22}

formula units (c)

6.70\times10^{22}

formula units (d)

6.70\times10^{21}

formula units