The subject is the question. Graphite is more stable than diamond and energy is needed to convert graphite into diamond. The extra energy that has to be provided ends up in the tetrahedral structure of diamond.
Is graphite to diamond endothermic?
Endothermic. Graphite and diamond are allotropic forms of the element Carbon. However, diamond cannot be formed at STP. While the energy of formation of graphite is zero, it is not so for diamond.
Does graphite to diamond increase entropy?
Yes, the entropy increases while changing from diamond to graphite.
What is the enthalpy change of graphite to diamond?
Given Cgraphite,△combH = -391.25 kJ; Cdiamond,△combH = -393.12 kJ.
Is converting diamond to graphite spontaneous?
At higher temperatures or under intense ion bombardment, the degradation of diamond to graphite becomes much faster. … At high pressure, diamond is the most stable configuration of pure carbon and not graphite. For this reason diamond spontaneously forms and does not degrade to graphite deep underground.
Which is more stable diamond or graphite?
At normal temperatures and pressures, graphite is only a few eV more stable than diamond, and the fact that diamond exists at all is due to the very large activation barrier for conversion between the two. … So diamond is said to be metastable, since it is kinetically stable, not thermodynamically stable.
Why enthalpy of graphite is lower than diamond?
Greater entropy of graphite is related to its structure as graphite is less compact and rigid than diamond. ΔH∘f for graphite is zero, but the ΔH∘f for diamond is 2kJ/mol. That is because graphite is the standard state for carbon, not diamond.
Would a low or a high temperature Favour the conversion of graphite into diamond?
Thus, high temperature and high pressure favors the formation of diamond from graphite.
What type of mineral is graphite?
Graphite is a naturally occurring form of crystalline carbon. It is a native element mineral found in metamorphic and igneous rocks. Graphite is a mineral of extremes. It is extremely soft, cleaves with very light pressure, and has a very low specific gravity.
What will be the sign of entropy change when carbon diamond changes to carbon graphite?
d)CaCO3(s)-CaO(s)+ CO2(g) The entropy decreases in the above conversion because diamond has a more orderly arrangement of atoms as compared to graphite. So the entropy will have a negative sign. … So the change in entropy will be positive.
What will be the enthalpy change?
The heat that passes into or out of the system during a reaction is the enthalpy change. … The enthalpy change of a reaction is roughly equivalent to the amount of energy lost or gained during the reaction. A reaction is favored if the enthalpy of the system decreases over the reaction.
What is the enthalpy change of graphite conversion?
Answer: The enthalpy change in the conversion of 10 g graphite in diamond is 0.375 kcal. The enthalpy change in the conversion of 10 g graphite in diamond is 0.375 kcal.
What is the enthalpy of combustion of carbon to produce carbon monoxide?
The enthalpies of combustion of carbon and carbon monoxide are -390 kJ mol^(-1) and -278 kJ mol^(-1) respectively.
How long will a diamond last?
You see, all the Diamonds in the Jewelry Stores Today were Created Billions of years ago. So for a Diamond to Last for a Billion Years, that Pretty Much says “YES, Diamonds DO Last Forever!” After all, Diamonds are the Hardest Known Substance made in Nature (a 10 on the Moh’s Scale).
Is a diamond really forever?
Diamonds do not last forever. Diamonds degrade to graphite, because graphite is a lower-energy configuration under typical conditions. … Diamond is therefore a metastable state. As is always the case in chemistry, energy must be inputted to break chemical bonds and allow new bonds to form.
Why does diamond not conduct electricity but is very strong?
Diamond is a giant covalent structure; each valence electron (outer shell electron) of every carbon atom forms a covalent bond, which means that there are no free electrons. Since electrical conductivity relies on the flow of free electrons, diamond is not a good conductor.