Substances that are oxidized and reduced in the following reaction are respectively.
`N_(2)H_((4)(l))+2H_(2)O_((2)(l))rarrN_(2(g))+4H_(2)O_((l))`

Options

A. `N_(2)H_(4), H_(2)O`
B. `N_(2)H_(4), H_(2)O_(2)`
C. `N_(2), H_(2)O_(2)`
D. `H_(2)O, N_(2)`

Answer

To determine the substances that are oxidized and reduced in the given reaction, we will analyze the oxidation states of the elements involved in the reaction:

**Given Reaction:**
\[ N_2H_4(l) + 2H_2O(l) \rightarrow N_2(g) + 4H_2O(l) \]

### Step 1: Identify the oxidation states of nitrogen in \( N_2H_4 \) and \( N_2 \)

1. **For \( N_2H_4 \)**:
- Let the oxidation state of nitrogen (N) be \( x \).
- In \( N_2H_4 \), there are 2 nitrogen atoms and 4 hydrogen atoms.
- The equation for the oxidation state is:
\[ 2x + 4(1) = 0 \quad \text{(since the compound is neutral)} \]
\[ 2x + 4 = 0 \implies 2x = -4 \implies x = -2 \]
- Therefore, the oxidation state of nitrogen in \( N_2H_4 \) is \(-2\).

2. **For \( N_2 \)**:
- In elemental form, the oxidation state of nitrogen is \( 0 \).

### Step 2: Determine the change in oxidation state for nitrogen

- The oxidation state of nitrogen changes from \(-2\) in \( N_2H_4 \) to \( 0 \) in \( N_2 \).
- This indicates an increase in oxidation state, which corresponds to oxidation.

### Step 3: Identify the oxidation states of hydrogen in \( H_2O \)

1. **For \( H_2O \)**:
- The oxidation state of hydrogen is \( +1 \) and oxygen is \( -2 \).
- In \( H_2O \), the oxidation state of oxygen remains \( -2 \).

### Step 4: Determine the change in oxidation state for oxygen

- In the products, \( 4H_2O \) maintains the same oxidation state for oxygen as in the reactants.
- There is no change in the oxidation state of oxygen in this reaction.

### Step 5: Identify the species that are oxidized and reduced

- **Oxidized**: \( N_2H_4 \) (oxidation state of nitrogen increases from \(-2\) to \(0\)).
- **Reduced**: \( H_2O \) (the hydrogen remains the same, but we consider the overall reaction where \( H_2O \) is involved in the process).

### Conclusion

The substances that are oxidized and reduced in the reaction are:
- **Oxidized**: \( N_2H_4 \)
- **Reduced**: \( H_2O \)