I think the correct answer would be the third option. The reason I2 has a higher melting point than F2 is because I2 possesses a more polarizable electron cloud. I2 contains more electrons than F2 which would result to a stronger intermolecular forces. Having stronger intermoleculer forces would mean more energy is needed to break the bonds so a higher melting point would be observed.
<span>As mentioned, the isomerization of cyclopropane to propylene is a first-order process with a half-life of 19 min at 500°c. A first-order reaction kinetic rates means that the rate is constant throughout the reaction.
Thus, the time it takes for the partial pressure of cyclopropane to decrease from 1 atm to 0.125 atm at 500°c is </span><span>57 minutes.</span>
