Question

Giúp mình câu 3

Answer 1

Câu 3:

\(a,PTHH:2Mg+O_2\rightarrow2MgO\\ b,n_{Mg}=\dfrac{4,8}{24}=0,2\left(mol\right)\\ \Rightarrow n_{MgO}=0,2\left(mol\right)\\ \Rightarrow m_{MgO}=0,2\cdot40=8\left(g\right)\\ c,\text{Bảo toàn KL: }m_{O_2}=m_{MgO}-m_{Mg}=3,2\left(g\right)\)