Odd One Out: Graphite (Option D)

Explanation:

Coke, charcoal, carbon black, and graphite are all allotropes of carbon, which means they are different forms of carbon with different physical and chemical properties. However, graphite is the odd one out among these options.

1. Coke:
- Coke is a porous form of carbon that is produced by heating coal in the absence of air. It is grayish-black in color and has a high carbon content.
- It is used primarily as a fuel and in the production of steel. It is also used in the manufacture of electrodes for electric arc furnaces and in the production of chemicals.

2. Charcoal:
- Charcoal is another form of carbon that is produced by heating organic materials (such as wood or coconut shells) in the absence of air. It is black in color and has a lower carbon content compared to coke.
- Charcoal is commonly used as a fuel for cooking and heating, as well as in the production of activated carbon for various applications including water purification, air filtration, and medicine.

3. Carbon Black:
- Carbon black is a fine powder of carbon particles that is produced by the incomplete combustion of hydrocarbons. It is black in color and has a high carbon content.
- Carbon black is used as a reinforcing filler in rubber products, as a pigment in inks and paints, and as a conductive agent in batteries and electronic devices.

4. Graphite:
- Graphite is a crystalline form of carbon that is composed of layers of carbon atoms arranged in a hexagonal lattice. It is grayish-black in color and has a very high carbon content.
- Graphite is known for its unique properties, including its lubricity, electrical conductivity, and thermal conductivity. It is used in a wide range of applications, such as in pencils, lubricants, electrodes, and as a material for nuclear reactors.

Conclusion:
While coke, charcoal, and carbon black are all forms of carbon that are primarily used as fuels or additives in various industries, graphite stands out as it has distinct properties and applications. Graphite's crystalline structure and unique properties make it a valuable material in many industries, setting it apart from the other options.