Question

помогите срочно...!!​

Answer 1

1.
Mr(KCl)=29+35,5=39+36=75
Mr(Al2(SO4)3=2*27+3*32+12*16=342

2.
AsH3. As(III) H(I)
SiH4. Si(IV) H(I)
PbO. Pb(II) O(II)
SO3. S(VI) O(II)
P2O5. P(V) O(II)
MnO2. Mn(IV) O(II)

3.
2MgO+O2=2MgO
4P+5O2=2P2O5
2H2S+O2=2S+2H2O
2KMnO4=K2MnO4+MnO2+O2

4.
2Cr+3O2=2CrO3
Fe+2HCl=FeCl2+H2
2AgOH=Ag2O+H2O