A gas initially at 30C must be changed to ? C to triple the pressure.
I think Bob Pursley answered this question either early this a.m. or yesterday. My answer is not the same method but it will work also.
Use PV = nRT
You can assume V, n, and you know R. Plug in T for 30 degrees C but change to Kelvin first.
Now use the same V and n, triple the pressure you initially used, and calculate the new T. Convert Kelvin, then, to C. Post your work if you get stuck.
i still don't get it...
what am i suppose to assume for V and n?
To find the final temperature, we need to determine the change in temperature required to triple the pressure of the gas. The pressure of a gas is directly proportional to its temperature when the volume and amount of gas remain constant (according to the ideal gas law).
To triple the pressure, we can set up the following equation:
P1/T1 = P2/T2
where P1 is the initial pressure, T1 is the initial temperature, P2 is the final pressure (triple the initial pressure), and T2 is the final temperature we want to find.
Let's assign some values:
- Initial temperature (T1) = 30°C (or you can convert it to Kelvin by adding 273.15, which gives T1 = 303.15 K)
- Initial pressure (P1) = given or needs to be known
- Final pressure (P2) = triple the initial pressure
- Final temperature (T2) = the value we need to find
Since we don't have the initial pressure value, we can solve the equation in terms of P1 and T2:
P1/T1 = (3P1)/T2
Now we can cross-multiply and solve for T2:
P1 * T2 = 3P1 * T1
Divide both sides by P1:
T2 = 3T1
Substitute the value of T1:
T2 = 3 * 30°C = 90°C
So, the gas needs to be changed to 90°C to triple the pressure.