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Why is graphite used in pencils and electric furnace electrodes?

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A color-coded periodic table of the elements displays each element's symbol and atomic number, with categories such as alkali metals, noble gases, halogens, transition metals, and actinoid elements distinguished by different background colors. — carbon group element Modern version of the periodic table of the elements (printable).

Graphite is used in pencils and electric furnace electrodes due to its unique physical and chemical properties, which are derived from its layered crystal structure.12

Use in Pencils

Graphite is ideal for writing because it is very soft and possesses lubricating properties, allowing it to leave a dark mark on paper as layers of carbon atoms easily slide off and deposit onto the surface. The name "graphite" itself is derived from the Greek verb graphein, meaning "to write". By mixing graphite with varying proportions of clay, manufacturers can control the hardness of the "lead" to produce different shades and line qualities.123

Use in Electric Furnace Electrodes

Graphite is a critical material for electrodes in electric arc furnaces because it is an excellent conductor of electricity and heat. Its ability to withstand high temperatures and its high thermal conductivity make it highly effective for the intense conditions required in steelmaking. These properties, combined with its structural stability, allow it to function reliably as an electrode in industrial applications.12