\(S=\dfrac{53}{250}\cdot100=21,2\left(g\right)\\ C_{\%}=\dfrac{53}{53+250}\cdot100\%=17\%\)
\(S=\dfrac{53}{250}\cdot100=0,212\left(g\right)\\m_{dd}=53+250=303\left(g\right)\\ C_{\%}=\dfrac{53}{303}\cdot100\%=17\%\)
`S_{Na_2CO_3}` = `53/250` . 100 = 21,2g
`C%` = `53/{53 + 250}` . 100`%` = 17,492`%`