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Is there lead in a pencil?

“Pencil "lead" doesn't contain any lead. It's made of graphite, a form of carbon, mixed with clay.”

Reference: Royal Society of Chemistry

What saturation of sulfur dioxide will cause people to cough

Sulfur dioxide is a colorless gas with a suffocating, choking odor. It is toxic to humans and concentrations as low as 8 ppm will produce coughing. Incredibly, in the Odyssey, Homer describes the burning of sulfur (formation of SO2) as a way that homes were 'fumigated'.

What do diamonds and pencil lead have in common?

Diamonds and graphite, the "lead" in pencils, are both made entirely of carbon. The only difference is how their atoms are arranged.

Who created the periodic table of elements?

Russian chemist Dmitri Mendeleev published his periodic table in 1869. He left gaps for elements that had not been discovered yet and correctly predicted their properties.

Another fact

“Pencil "lead" doesn't contain any lead. It's made of graphite, a form of carbon, mixed with clay.”

More from this shelf

What saturation of sulfur dioxide will cause people to cough

What do diamonds and pencil lead have in common?

Who created the periodic table of elements?