Complete the following reaction :
`C`(graphite) + `HNO_(3)` (conc.) `to`

Answer

To complete the reaction between graphite (C) and concentrated nitric acid (HNO₃), we follow these steps:

### Step 1: Identify the Reactants
The reactants in this reaction are:
- Graphite (C)
- Concentrated Nitric Acid (HNO₃)

### Step 2: Determine the Products
When graphite reacts with concentrated nitric acid, it produces:
- Carbon Dioxide (CO₂)
- Nitrogen Dioxide (NO₂)
- Water (H₂O)

### Step 3: Write the Unbalanced Equation
The unbalanced chemical equation for the reaction can be written as:
\[ \text{C} + \text{HNO}_3 \rightarrow \text{CO}_2 + \text{NO}_2 + \text{H}_2\text{O} \]

### Step 4: Balance the Chemical Equation
To balance the equation, we need to ensure that the number of atoms of each element is the same on both sides.

1. Start with carbon (C):
- There is 1 carbon atom on the left (from graphite) and 1 on the right (in CO₂).

2. Next, balance the nitrogen (N):
- Each molecule of HNO₃ contains 1 nitrogen atom. We will need 4 nitrogen atoms to produce 4 NO₂, so we need 4 HNO₃.

3. Now, balance the hydrogen (H):
- From 4 HNO₃, we have 4 hydrogen atoms. To balance this, we need 2 H₂O (which gives us 4 hydrogen atoms).

4. Finally, balance the oxygen (O):
- On the right side, we have:
- 2 from CO₂
- 8 from 4 NO₂ (4 x 2)
- 2 from 2 H₂O (2 x 1)
- Total = 2 + 8 + 2 = 12 oxygen atoms
- On the left side, from 4 HNO₃, we have 12 oxygen atoms (4 x 3).

### Step 5: Write the Balanced Equation
The balanced chemical equation is:
\[ \text{C} + 4 \text{HNO}_3 \rightarrow \text{CO}_2 + 4 \text{NO}_2 + 2 \text{H}_2\text{O} \]

### Final Answer:
The complete balanced reaction is:
\[ \text{C} + 4 \text{HNO}_3 \rightarrow \text{CO}_2 + 4 \text{NO}_2 + 2 \text{H}_2\text{O} \]

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