An ideal gas in a sealed container has an initial volume of 2.35 L. At constant pressure, it is cooled to 23.00 ∘ C , where its final volume is 1.75 L. What was the initial temperature?

397.5K

Explanation:

Given parameters:

Initial volume = 2.35L

Final temperature = 23°C

Final volume = 1.75L

Unknown:

Initial temperature = ?

Solution:

The Charles's law states that "the volume of a fixed mass(mole) of a gas varies directly as its absolute temperature if the pressure is constant".

Mathematically;

where V₁ is the initial volume

           T₁ is the initial temperature

           V₂ is the final volume

           T₂ is the final temperature

we need to convert  °C to Kelvin;

         23°C; 273 + 23 = 296K

          T₁  = 397.5K

this is a good question! i'll do some research and come back when i have the answer!

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.