Answer:
Appearance and Color
Graphite is a dark gray to black, very soft, shiny metallic mineral with a distinctive greasy feeling. One of the Earth's softest minerals, graphite will easily leave marks on paper, which is why it is used for fine artist pencils. Even modern pencil 'lead' is composed of graphite mixed with clay.
Appearance and Color
Typically yellow, brown, or gray to colorless. Less often blue, green, black, translucent white, pink, violet, orange, purple, and red. Diamond is a solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic.
Melting Point
Graphite has a melting point similar to that of diamond of around 3600°C, at which point it sublimes rather than melting.
Melting Point
Diamond has a very high melting point (almost 4000°C). Very strong carbon-carbon covalent bonds have to be broken throughout the structure before melting occurs.
Solubility
Soluble in molten nickel, warm chlorosulfuric acid
Solubility
Resistant to acids, but dissolves irreversibly in hot steel
Strength
Although graphite is flexible, it is not elastic and has high electrical and thermal conductivity. It is also chemically inert and highly refractory.
Strength
Diamond is a form of carbon that is crystallised in a cubic structure with each carbon atom linked by a strong, rigid chemical bond to four other atoms.
CONDUCT ELECTRICITY
Graphite has delocalised electrons, just like metals. These electrons are free to move between the layers in graphite, so graphite can conduct electricity.
CONDUCT ELECTRICITY
Diamond is a form of carbon in which each carbon atom is joined to four other carbon atoms, forming a giant covalent structure. As a result, diamond is very hard and has a high melting point. It does not conduct electricity as there are no delocalised electrons in the structure.
USES
Graphite is used in pencils and lubricants. It is a good conductor of heat and electricity. Its high conductivity makes it useful in electronic products such as electrodes, batteries, and solar panels.
USES
The most familiar uses of diamonds today are as gemstones used for adornment, and as industrial abrasives for cutting hard materials. The markets for gem-grade and industrial-grade diamonds value diamonds differently.
