Mass of [tex]$\mathrm{Na}{2} \mathrm{CO} 3$[/tex] required [tex]$=0.55 \mathrm{~g}$[/tex]
The mass 0.120M HCI:
Moles of [tex]$\mathrm{HCl}$[/tex]reacted [tex]$=0.120 \times 21.6 / 1000=0.00260$[/tex]
according to balanced reaction, [tex]$\mathrm{HCl}$ and $\mathrm{Na} 2 \mathrm{CO} 3$[/tex] reacts in [tex]$2: 1$[/tex] the ratio
moles of [tex]$\mathrm{Na} 2 \mathrm{CO} 3$[/tex]required [tex]$=0.00260 \times 2=0.00520$[/tex]
convert moles to mass
mass [tex]$=$[/tex]moles [tex]$\times$[/tex]molar mass
mass [tex]$=0.00520 \times 106.0$[/tex]
mass [tex]$=0.55 \mathrm{~g}$[/tex]
mass of [tex]$\mathrm{Na} 2 \mathrm{CO} 3$[/tex]required [tex]$=0.55 \mathrm{~g}$[/tex]
Mass 0.120M HC is [tex]$=0.55 \mathrm{~g}$[/tex]
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