Question

A sample of neon initially has a volume of 2.50 L at 15°C. What is the new temperature, in °C, when the volume of the sample is changed at constant pressure to 1250 mL?

a) -10°C
b) 15°C
c) 30°C
d) 45°C

Answer 1

To determine the new temperature in Celsius when the volume of neon changes at constant pressure, Charles's Law is applied. The temperature is first converted to Kelvin, the law is applied using the given volumes, and the final temperature is converted back to Celsius.

Step-by-step explanation:

The subject of this question is Chemistry, specifically involving the concept of gas laws as it pertains to changes in temperature and volume. The problem is at a high school level. To find the new temperature when the volume of a gas is changed at constant pressure, we can use Charles's Law. Charles's Law states that the volume of a gas is directly proportional to its temperature in kelvins, assuming that the pressure and the amount of the gas are constant. The formula is given by V1/T1 = V2/T2, where V1 and T1 are the initial volume and temperature, and V2 and T2 are the final volume and temperature respectively.

To solve the problem:

1. Convert all temperatures to Kelvin by adding 273.15
2. Apply Charles's Law: V1/T1 = V2/T2
3. Plug in the values: (2.50 L) / (15°C + 273.15) = (1.25 L) / T2
4. Solve for T2
5. Subtract 273.15 from T2 to convert back to Celsius

Following these steps should yield the correct answer to the question.