Question

1) Why don't diamonds convert to graphite under ambient pressures, even though diamonds are thermodynamically less stable than graphite?

Answer 1

Ans : Diamonds cannot be converted to graphite under ambient pressures, even if diamonds are thermodynamically less stable than graphite. Since we know that the conversion from one form to another depends on many parameters not only stability factor , in this case the conversion depends upon the Activation barrier , which is too high in case of diamond .if even at high temprature if sufficient oxygen is provided diamond is converted into carbon di oxide (CO2), But cannot be converted into graphite due to high activation barrier . Due to this property diamond is metastable .