: Methylene Chloride has a boiling point of 40°C, and the melting point of methylene chloride is -96.7°C. What is (are) the state(s) of methylene chloride at 25°C? A. Solid and Liquid B. Solid C. Liquid and Gas D. Liquid
The Correct Answer and Explanation is:
At 25°C, methylene chloride (CH₂Cl₂) would be in a liquid state.
Explanation:
Methylene chloride has the following physical properties:
- Boiling point: 40°C
- Melting point: -96.7°C
The state of a substance is determined by its temperature relative to its melting point (solid-liquid transition) and boiling point (liquid-gas transition). Here’s the reasoning:
- At 25°C, which is well above the melting point (-96.7°C) but below the boiling point (40°C), methylene chloride is in its liquid state.
- Since 25°C is above the melting point, the solid form of methylene chloride will have already melted into a liquid.
- 25°C is also below the boiling point (40°C), so methylene chloride will not have vaporized into a gas.
- Solid state: This would only occur if the temperature were below the melting point of -96.7°C, which is far colder than 25°C.
- Gas state: This would only occur if the temperature were above the boiling point of 40°C, which is also not the case at 25°C.
Thus, at 25°C, methylene chloride is exclusively in the liquid state.
Correct Answer: D. Liquid
