Question

A student forgot to add the reaction mixture to the round bottomed flask at 27 °c but instead he/she placed the flask on the flame. After a lapse of time, he realized his mistake, and using a pyrometer he found the temperature of the flask was 477 °c. What fraction of air would have been expelled out?

Answer 1

Let the volume of the round-bottomed flask be V.

Then, the mass of air inside the flask at 27° C is V.

Now,

V1 = V

T1 = 27°C = 300 K

V2 =?

T2 = 477° C = 750 K

According to Charles’s law,

V1/T1 = V2/T2

=> V2 =V1T2/T1

         = V(750/300)

        = 2.5 V

So, volume of air expelled out = 2.5 V – V = 1.5 V

Hence, fraction of air expelled out = (1.5 V)/2.5 V) = 3/5

Answer 2

Answer:

I hope this is the correct answer .