Решите все дам 30 баллов

40) M(CuO)=63.5+16=79.5 g/mol W(Cu)=63.5/79.5*100%=79.87% W(O)=16/79.5*100%=20.13% 41) M(H2S)=1*2+32=34 g/mol W(H)=1*2/34*100%=5.88% W(S)=32/34*100%=94.12% M(CH4)=12+1*4=16 g/mol w(C)=12/16*100=75% W(H)=1*4/16*100%=25% 42) M(HNO3)=1+14+16*3=63 g/mol W(H)=1/63*100%=1.59% W(N)=14/63*100%=22.22% W(O)=16*3/63*100%=76.19% M(H2SO4)=1*2+32+16*4=98 g/mol W(H)=1*2/98*100%=2.04% W(S)=32/98*100%=32.65% W(O)=16*4/98*100%=65.31%