At a temperature of $27\,^oC$ and a pressure of $1\,atm$,the density of a gas is $d$. At constant pressure,at what temperature will its density become $0.75\,d$?

In a closed vessel,an ideal gas at $1 \, atm$ is heated from $27^{\circ} C$ to $327^{\circ} C$. The final pressure of the gas will approximately be $..... \, atm$

What is called an ideal gas? Why?

An open vessel at $27\,^oC$ is heated such that $\frac{3}{5}$ of the air in it is expelled. Assuming the volume of the vessel remains constant,calculate the temperature in $K$ to which the vessel was heated.

State the combined gas law and the ideal gas equation.

$A$ student forgot to add the reaction mixture to the round bottomed flask at $27^{\circ} C$ 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 $477^{\circ} C$. What fraction of air would have been expelled out?