$\therefore $ $1$ molecule ${C_{60}}{H_{122}}$ has mass $\frac{{842}}{{6 \times {{10}^{23}}}}$
$ = 140.333 \times {10^{ - 23}}gm$ $ = 1.4 \times {10^{ - 21}}\,gm$.
$CaCO _{3( s )}+2 HCl _{( aq )} \rightarrow CaCl _{2( aq )}+ CO _{2( g )}+2 H _{2} O _{( l )}$
[બે દશાંશ બિંદુ સુધી ગણતરી કરો]