Ammonium dichromate is used in some fireworks. The green-coloured powder blown in the air is

Options

A. `CrO_(3)`
B. `Cr_(2)O_(3)`
C. `Cr`
D. `CrO(O_(2))`

Explanation

To solve the question regarding the green-colored powder produced from ammonium dichromate in fireworks, we can follow these steps:

### Step 1: Identify the Reactants
The reactants in this scenario are ammonium dichromate, which has the formula \( \text{(NH}_4)_2\text{Cr}_2\text{O}_7 \).

### Step 2: Write the Reaction
When ammonium dichromate is heated, it decomposes into chromium(III) oxide, nitrogen gas, and water. The balanced chemical equation for this reaction is:

\[ \text{(NH}_4)_2\text{Cr}_2\text{O}_7 \rightarrow \text{Cr}_2\text{O}_3 + \text{N}_2 + \text{H}_2\text{O} \]

### Step 3: Identify the Products
From the balanced equation, we can see that one of the products is chromium(III) oxide, which has the formula \( \text{Cr}_2\text{O}_3 \). This compound is known for its green color.

### Step 4: Conclusion
The green-colored powder that is blown into the air during the fireworks is chromium(III) oxide, \( \text{Cr}_2\text{O}_3 \).

### Final Answer
The correct answer is \( \text{Cr}_2\text{O}_3 \).

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