If decomposition of 1 mole of ethylene with a gas density of 0.215g/mL starts at 29 degree celcius and the temperature increases by 950K, what is the final pressure of the confined gas?

We calculate first the initial pressure of the gas.

P = nRT/V

= (0.215 g/mL) (1 mol/16 g) (0.0821 L. atm/mol K) (302K)

= 0.333 atm

Using the relationship between the pressure and temperature,

P1/T1 = P2/T2

Substituting the known values,

(0.333 atm) / (29 + 273) = P2 / (950)

P2 = 1.05 atm