"NUCLEAR POWER" produces "no air pollution".
Option: D
<u>Explanation</u>:
As nuclear power does not emit any hazardous gas or smoke thus it produces no air pollution. But disposing of the waste is still a big issue in the case of nuclear power for which usually underground disposal in appropriate container method is opted but it's too have many disadvantages. Threat of an accident and the expenses of constructing nuclear reactors are really high so other three options are disadvantages of nuclear power.
<em>Diamond and graphite are allotropes of carbon and have various differences in their physical properties.</em>
Explanation:
<u>Diamond:</u>
- It is crystalline in nature
- Each Each C is
hybridized and forms 4 covalent binds with neighboring C atoms - The geometry is tetrahedral
- C-C bond length is 154 pm
- It has rigid covalent boning which is difficult to break.
- It acts as an electric insulator
<u>Graphite:</u>
-
It has layered structure
- Each C atom is sp2 hybridized and forms 3 sigma bonds with 3 other C atoms. Fourth electron forms pi bond.
-
The geometry is planar
- C-C bond length is 141.5 pm
- It is soft. Its layers can be separated easily
- It is good conductor of electricity.
This is the comparison of the physical properties of two forms of carbon: diamond and graphite
It is a reaction that requires heat as a reactant.
Hopefully this will help Im pretty sure this is the answer