A block of ice at `-5^@C` is slowly heated and converted to steam at `100^@C` . The process can be qualitatively represented by the curve

Options

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Explanation

To solve the problem of heating a block of ice at -5°C and converting it to steam at 100°C, we can break down the process into several steps and represent it graphically. Below is the step-by-step solution:

### Step 1: Identify the Initial and Final States
- **Initial State**: Ice at -5°C
- **Final State**: Steam at 100°C

### Step 2: Understand the Heating Process
The process involves several stages:
1. Heating the ice from -5°C to 0°C (sensible heat).
2. Melting the ice at 0°C to water (latent heat).
3. Heating the water from 0°C to 100°C (sensible heat).
4. Converting the water at 100°C to steam (latent heat).
5. Heating the steam from 100°C to a higher temperature (if needed, but in this case, we stop at 100°C).

### Step 3: Calculate the Heat Transfer for Each Stage
1. **Heating Ice from -5°C to 0°C**:
- Use the formula: \( Q_1 = m \cdot c_{ice} \cdot \Delta T \)
- Where \( c_{ice} \) is the specific heat capacity of ice and \( \Delta T = 0 - (-5) = 5°C \).

2. **Melting Ice at 0°C**:
- Use the formula: \( Q_2 = m \cdot L_f \)
- Where \( L_f \) is the latent heat of fusion.

3. **Heating Water from 0°C to 100°C**:
- Use the formula: \( Q_3 = m \cdot c_{water} \cdot \Delta T \)
- Where \( c_{water} \) is the specific heat capacity of water and \( \Delta T = 100 - 0 = 100°C \).

4. **Converting Water at 100°C to Steam**:
- Use the formula: \( Q_4 = m \cdot L_v \)
- Where \( L_v \) is the latent heat of vaporization.

5. **Total Heat Transfer**:
- The total heat \( Q_{total} = Q_1 + Q_2 + Q_3 + Q_4 \).

### Step 4: Graphical Representation
- On a graph with temperature on the y-axis and heat on the x-axis:
- From -5°C to 0°C, draw a sloped line (sensible heat).
- From 0°C to 0°C (phase change), draw a horizontal line (latent heat).
- From 0°C to 100°C, draw another sloped line (sensible heat).
- From 100°C to 100°C (phase change), draw another horizontal line (latent heat).

### Step 5: Conclusion
The graph represents the heating process of ice at -5°C to steam at 100°C, showing both sensible and latent heat transfers.