Mentre or quando, what is the difference?

Question

I am using Duolingo to learn Italian and I came across this translation exercise: "I eat when I want". I answered: "mangio mentre voglio". However it is marked wrong. The right answer is: "mangio quando voglio". Can someone please show me the difference between the two?

Answer 1

• Quando means when

• Mentre means while.

Would you say "I eat while I want" or "...when I want"?

(same difference as in English)