Question

`I am holding a balloon containing 439 mL of gas over my fireplace. The temperature and pressure of the gas inside the balloon is 317.15 K and 0.959 atm, respectively. Suppose I don't want the pressure to change, but I want to the volume to go down to 0.378 L. What is the temperature that I need to reach when I cool down the balloon? To what temperature (in Celsius) must the balloon be cooled to reduce its volume to 0.378 L if the pressure doesn't change (remained constant)?

Answer 1

Answer:

- 0.07 °C

Explanation:

At constant pressure and number of moles, Using Charle's law  

$\frac {V_1}{T_1}=\frac {V_2}{T_2}$

Given ,  

V₁ = 439 mL  = 0.439 L ( 1 L = 0.001 mL )

V₂ = 0.378 L

T₁ = 317.15 K

T₂ = ?

Using above equation as:

$\frac{0.439}{317.15}=\frac{0.378}{T_2}$

$T_2=\frac{0.378\cdot \:317.15}{0.439}=273.08\ K$

The conversion of T(K) to T( °C) is shown below:

T( °C) = T(K) - 273.15  

So, T = 273.08 - 273.15 °C = - 0.07 °C