Question

To what temperature must a balloon, initially at 9°C and 4.00 L, be heated in order to have a volume of 6.00 L? 0 13.5K O6K 423K 188 K O 993K

Answer 1

Actually, from ideal gas law i.e., pV=nRT ​​​​​​, it can be observed that as temperature increase pressure should increase and volume should also increase but here in this situation since pressure is constant and equal to atmospheric pressure. So, Volume increases with increasing pressure.

In such cases where the walls of container i.e.,balloon is flexible the volume changes with change in temperature, keeping the pressure in the inside and outside constant. The volume thus increases by pushing the walls of balloon such that pressure inside the balloon becomes equal to that of atmospheric pressure.

Here in the question we are provided

Initial temperature, T_i =9°C = (273+9)K = 282K

Initial Volume, V_O= 4 L

Final Volume, V_f = 6L

Thus, By following the ideal gas equation, we get

p V = n R T

Here, number of moles, n is constant and Pressure, p is constant.

So, we can modify the equation as

p/nR = T/V

Thus,  constant = T/V

   T₁/V₁= T₂/V₂

  T₂ = T₁.V₂ / V₁

  T₂ = 282 K × 6L / 4L = 282K × 1.5 = 423K