General Knowledge - General Science - Discussion

What is meant by lubricant?

Graphite contains layers of carbon atoms. The layers slide over each other easily because there are only weak forces between them, making graphite slippery. Graphite contains delocalised electrons (free electrons).

Graphite have more space between their atoms and have smooth bonding that's why the graphite are always smooth in surfaces.

Graphite used in atomic reactors as a slow atomic reactions as coolent.

Is a necessary component for graphite lubrication. The adsorption of water reduces the bonding energy between the hexagonal planes of the graphite to a lower level than the adhesion energy between a substrate and the graphite. Because water vapour is a requirement for lubrication, graphite is not effective in a vacuum. Because it is electrically conductive, graphite can promote galvanic corrosion.

Graphite is the 'gray lead in your drawing pencil. Graphite is not lead at all; the misnomer arose because it was mistaken for a form of leGraphite is best suited for lubrication in air. Water vapour is a necessary component for graphite lubrication. The adsorption of water reduces the bonding energy between the hexagonal planes of the graphite to a lower level than the adhesion energy between a substrate and the graphite. Because water vapour is a requirement for lubrication, graphite is not effective in a vacuum. Because it is electrically conductive, graphite can promote galvanic corrosion. In an oxidative atmosphere, graphite is effective at high temperatures up to 450° C continuously and can withstand much higher temperature peaks.

Ad when first discovered in England. Graphite is, in fact, a form of carbon, and is non-toxic. Pencils have never been made from lead, but it was not until the late 18th century that the true composition of the material was identified, and the original name stuck. Modern pencil cores contain an extruded blend of pulverised graphite and clay.

Graphite use as control rod or lubricant in a nuclear reactor?

Thank you all for explaining the answer.

How can we say that only graphite is used as lubricant, silica is also used as lubricant without any clarification in question?

We can use many such things as lubricants. Why only silica gel?