Heat energy can be supplied to a substance without increasing its temperature.

Answer

**Step-by-Step Solution:**

1. **Understanding Heat Energy and Temperature:**
- Heat energy can be added to a substance without causing a change in its temperature. This phenomenon occurs during phase changes.

**Hint:** Remember that temperature measures the average kinetic energy of particles, while heat energy is the total energy transferred.

2. **Phase Changes:**
- When a substance undergoes a phase change, such as melting or boiling, the heat energy supplied is used to change the state of the substance rather than increasing its temperature.
- For example, when ice (solid) is heated, it eventually reaches 0°C (the melting point) and begins to melt into water (liquid) without a temperature increase.

**Hint:** Identify the specific temperatures at which phase changes occur for different substances.

3. **Melting of Ice:**
- As heat is supplied to ice, its temperature rises from below 0°C to 0°C. At 0°C, the ice starts to melt. During this melting process, the temperature remains constant at 0°C even though heat is still being added.

**Hint:** Consider the energy required for melting (latent heat of fusion) and how it affects temperature.

4. **Boiling of Water:**
- After all the ice has melted into water, if heat continues to be supplied, the temperature of the water will start to increase until it reaches 100°C (the boiling point). At this point, the water will begin to boil, and again, the temperature will remain constant during the boiling process.

**Hint:** Recall the concept of latent heat of vaporization for the transition from liquid to gas.

5. **Conclusion:**
- In summary, heat energy can be supplied to a substance without increasing its temperature during phase changes (solid to liquid, liquid to gas). The energy goes into changing the state of the substance rather than raising its temperature.

**Hint:** Reflect on how this principle applies to everyday experiences, such as ice melting or water boiling.

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