With the aid of chemical equations identify two chemical that are commonly used in the laboratory to prepare oxygen gas?

1. Hydrogen peroxide (H2O2) is commonly used in the laboratory to prepare oxygen gas. The decomposition of hydrogen peroxide produces oxygen gas and water:

2H2O2 (l) → 2H2O (l) + O2 (g)

2. Potassium chlorate (KClO3) is another common chemical used in the laboratory to prepare oxygen gas. When potassium chlorate is heated, it decomposes to produce oxygen gas and potassium chloride:

2KClO3 (s) → 2KCl (s) + 3O2 (g)

1. Hydrogen peroxide (H2O2) decomposition:
```
2H2O2(l) → 2H2O(l) + O2(g)
```

2. Potassium permanganate (KMnO4) and sulfuric acid (H2SO4) reaction:
```
2KMnO4(aq) + 3H2SO4(aq) → K2SO4(aq) + 2MnSO4(aq) + 3H2O(l) + 5O2(g)
```