Question

Answer 1

Bài 3 : 

Đặt : CTHH của X : \(Al_xS_yO_z\)

Ta có : 

\(x:y:z=\dfrac{15.8}{27}:\dfrac{28.1}{32}:\dfrac{56.1}{16}=0.58:0.87:3.48=2:3:12\)

\(CT:Al_2S_3O_{12}\rightarrow Al_2\left(SO_4\right)_3\)

\(M=27\cdot2+96\cdot3=342\left(đvc\right)\)

 

Answer 2

Bài 4 : 

\(a.\)

\(Ca\left(H_2PO_4\right)_2+2Ca\left(OH\right)_2\rightarrow Ca_3\left(PO_4\right)_2+4H_2O\)

\(b.\)

\(3Mg+8HNO_3\rightarrow3Mg\left(NO_3\right)_2+2NO+4H_2O\)

\(c.\)

\(8Al+30HNO_3\rightarrow8Al\left(NO_3\right)_3+3N_2O+15H_2O\)