Вопрос школьника по предмету Химия
Запишите химические реакции, расставьте коэффициенты
1. Фосфор + кислород
2. Гидроксид калия + хлорид железа (3)
3. Цинк + соляная кислота
4. Хлорид алюминия + калия
5. Карбонат натрия + фосфорная кислота
Ответ учителя по предмету Химия
1) 4P + 5O2 = 2P2O5
2) 3КОН + FeCl3 = 3 КCl + Fe(OH)3
3) Zn+2HCl=ZnCL2+H2
4) AlCl3 + 3K = 3KCl + Al
5) 3Na2CO3 + 2H3PO4 = 2Na3PO4+3H2O+3CO2;
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