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Biochemistry

Comparison of the Properties of Diamond and Graphite

Diamond	Graphite
It occurs naturally in free state.	It occurs naturally and is manufactured
It occurs naturally in free state.	artificially.
	artificially.
It is the hardest natural substance known.	It is soft and greasy to touch.
It has high relative density (about 3.5).	Its relative density is 2.3.
It is transparent and has high refractive	It is black in color and opaque.
index (2.45).
It is non-conductor of heat and electricity.	Graphite is a good conductor of heat and
	electricity.
It burns in air at 900°C to give CO₂.	It burns in air at 700-800°C to give CO₂.
It occurs as octahedral crystals.	It occurs as hexagonal crystals.
It is insoluble in all solvents.	It is insoluble in all ordinary solvents

These differences in the properties of diamond and graphite are due to the difference in their structures. In diamond, each C atom is linked to its neighbors by four single covalent bonds. This leads to a three-dimensional network of covalent bonds. In graphite, the carbon atoms are arranged in flat parallel layers as regular hexagons.

Each carbon in these layers is bonded to three others by covalent bonds. Graphite thus acquires some double bond character. Each layer is bonded to adjacent layers by weak van der Waals forces. This allows each layer to slide over the other easily. Due to this type of structure graphite is soft and slippery, and can act as a lubricant.
Biochemistry
Biochemistry is the branch of science that explores the chemical processes within and related to living organisms. It is a laboratory based science that brings together biology and chemistry. By using chemical knowledge and techniques, biochemists can understand and solve biological problems.

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Biochemistry focuses on processes happening at a molecular level. It focuses on what’s happening inside our cells, studying components like proteins, lipids and organelles. It also looks at how cells communicate with each other, for example during growth or fighting illness. Biochemists need to understand how the structure of a molecule relates to its function, allowing them to predict how molecules will interact.

Biochemistry covers a range of scientific disciplines, including genetics, microbiology, forensics, plant science and medicine. Because of its breadth, biochemistry is very important and advances in this field of science over the past 100 years have been staggering. It’s a very exciting time to be part of this fascinating area of study.

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