Which is the hardest natural substance known?

GraphiteCorrect answerYour answerIronCorrect answerYour answerDiamondCorrect answerYour answerQuartzCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer C

Correct answer: C

Diamond is carbon with every atom bonded strongly to four others in a rigid three-dimensional network.
That makes it the hardest natural substance, used to cut glass and drill rock.

Ten questions from Everyday Chemistry, at your own pace.

Ten questions from Everyday Chemistry, at your own pace.

Explanation