1 mole of H2 gas is contained in a box of volume V=1.00 m3 at T1 = 300 K. The gas is heated to a temperature of T2 = 3000 K and the gas gets converted into a gas of hydrogen atoms. The final pressure would be (considering all gases to be ideal)

When the molecules break into atoms, the number of moles would become twice.Now, by ideal gas equationP = Pressure of gas,n = Number of molesR Gas constant,T TemperatureWe have pV= nRTAs volume (V) of the container is constant.As gases break, number of moles becomes twice of initial number.so n2=2n1So p∝nT⇒ p2p1=n2T2n1T1=2n1(3000)n1(300)=20⇒ p2=20p1Hence, final pressure of the gas would be 20 times the pressure initially.