Question

Anyone know these???

Answer 1

Not exactly sure how KUFCA works as I couldn't find any information about it online, but I can show how to calculate these and hopefully you will find it helpful.

p1V1 = p2V2 is Boyle's law. It indicates the relationship between the pressure and the volume of gas. p1V1 is the initial pressure and volume, while p2V2 is the new pressure and volume. Pressure of a gas a inversely propertional to the volume. While means, the higher the pressure is, the smaller the volume will be.

You can make use of this equation to substitute the numbers from the question.
0.25 and 25 is the initial volume and pressure, while 50 is the new pressure. So we can put them in the equation:

25 x 0.25 = 50 x p1

Calculate for p1 just how you would do on algebra.

6.25 = 50 x p1
6.25 / 50 = p1
p1 = 0.125 cm3

The answer for the first question is 0.125 cm3.

The second equation T1V2 = T2V1 (also V1/T1=V2/T2) is Charles' law. It indicates the relationship between the temperature (in Kelvin) and the volume of gas. They're directly proportional. Which means, the higher the temperature, the larger the volume will be.

Again, substitute.
1200 and 425 is the initial volume and temperature. Since the temperature is already in Kelvin, you don't have to change it (if you ever encounter a temperature in Celsius scale, add 273 to the temperature). And the new volume should be 1400.

1200/425 = 1400/T2
2.8235294118 = 1400/T2
2.8235294118T2 = 1400
T2 = 1400/2.8235294118
T2 = 495.83333333K

Therefore, the answer for the second question is approximately 496K.