Chemistry

Question Analysis
This question assesses the student's ability to determine the phase of a substance based on its temperature and pressure relative to its melting point.

Key Concept Explanation
The melting point is the temperature at which a solid changes to a liquid at a given pressure. Below the melting point, the substance remains in the solid phase.

Step-by-step Solution
1. Identify the given melting point of the substance, which is 50°C at 1 atm.
2. Compare the given temperature (45°C) to the melting point (50°C).
3. Since 45°C is below the melting point, the substance will ...