Question

[level max]

Cân bằng các PTHH sau: 

1) P + O2 −−→ P2O5

2) Ca(OH)2 + CO2 −−→ CaCO3 ↓ + H2O

3) K + H2O −−→ KOH + H2 ↑

4) Fe + HCl −−→ FeCl2 + H2 ↑

5) Al + H2SO4 −−→ Al2(SO4)3 + H2 ↑

6) Fe + S −−→ FeS

7) Al(OH)3 −−→ Al2O3 + H2O

8) HgO −−→ Hg + O2 ↑

9) CuCl2 + KOH −−→ Cu(OH)2 ↓ + KCl

10) Cu(OH)2 −−→ CuO + H2O

Answer 1

[GV Nguyễn Trần Thành Đạt]

\(4P+5O_2\rightarrow\left(t^o\right)2P_2O_5\\ Ca\left(OH\right)_2+CO_2\rightarrow CaCO_3\downarrow+H_2O\\ 2K+2H_2O\rightarrow2KOH+H_2\uparrow\\ Fe+2HCl\rightarrow FeCl_2+H_2\uparrow\\ 2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\uparrow\\ Fe+S\rightarrow\left(t^o\right)FeS\\ 2Al\left(OH\right)_3\rightarrow\left(t^o\right)Al_2O_3+3H_2O\\ 2HgO\rightarrow\left(450^oC-500^oC\right)2Hg+O_2\uparrow\\ CuCl_2+2KOH\rightarrow Cu\left(OH\right)_2\downarrow+2KCl\\ Cu\left(OH\right)_2\rightarrow\left(t^o\right)CuO+H_2O\)

Answer 2

[Mai Anh]

1. `4P + 5O_2 -> 2P_2O_5`

2.`Ca(OH)_2 + CO_2 -> CaCO_3 \downarrow + H_2O`

3. `2K +2 H_2O -> 2KOH + H_2  \uparrow`

4. `Fe + 2HCl -> FeCl_2 + H_2 \uparrow`

5. `2Al + 3H_2SO_4 -> Al_2(SO_4)_3 + 3H_2  \uparrow`

6. `Fe + S -> FeS`

7. `2Al(OH)_3 -> Al_2O_3 + 3H_2O`

8. `2HgO -> 2Hg + O_2 \uparrow`

9. `CuCl_2 + 2KOH -> Cu(OH)_2\downarrow + 2KCl`

10. `Cu(OH)_2 ->CuO + H_2O`