Question

Qual a porcentagem do mg no composto Mg CO³?

(Mg= 24, C= 12, O=16)

Answer 1

$\Large\boxed{\begin{array}{l}\sf m_{MgCO_3}=24+12+3\cdot16=84\,g/mol\\\sf\%~de~Mg=\dfrac{24}{84}\cdot100\%=28,57\%\end{array}}$