2HCI+2K=2KCI+H2
H2S+Ca=CaS+H2
2H3PO4+6Na=2Na3PO4+3H2
H2SO3+Mg=MgSO3+H2
H2SO4+Am(не знаю степень )
2HNO3+Zn=Zn(NO3)2+H2
6HNO3+2Cr=2Cr(NO3)3+3H2
H2SO3+Fe=FeSO3+H2
w = <span>Ar(X) * a </span> * 100%<span>
</span>
Mr вещ-ва
Mr (Fe2O3) = 56*2 + 16*3 = 160
w(O) = <span>16 * 3 </span> * 100% = 30 %<span>
</span>
160
Ответ: w(O) = 30 %
СН2−СН2−СН−СН2−СН3 + 2Na → CH2−CH2−CH−CH2−CH3 + H2↑
|__________|_______________________|__________|
ОН________ОН_____________________ONa______ONa
1) MgCo3 = MgO + Co2
Mg(OH)2 = MgO + H2O
2Mg + O2 = 2MgO
2Ch4 + 4O2 = 2Co2 + 4H2o
Оксиды:
4Na + O2 = 2Na2O
2Ca + O2 = 2CaO
4P + 5O2 = 2P2O5
C + O2 = CO2.
Соли:
Ca + 2C = CaC2
3CaO + P2O5 = Ca3(PO4)2
CaO + CO2 = CaCO3
P2O5 + 3Na2O = 2Na3PO4
Na2O + CO2 = Na2CO3