Why do onions make us cry and how does the reaction happen?

Onions make us cry because they release tiny air pockets that tickle our eyes.

When you cut an onion, you're breaking open its cells, and inside those cells are little air pockets filled with a strong-smelling liquid called sulfur compounds. These air pockets get released into the air when you slice through the onion.

Your eyes are very sensitive to this strong-smelling liquid, so they try to protect themselves by making you cry. It's like when something spicy gets in your eye, it makes you blink and tear up.

1. You start cutting the onion.
2. The sulfur compounds inside the onion are released as tiny air pockets into the air.
3. These air pockets reach your eyes.
4. Your eyes feel like they're being tickled by something strong, so they send out tears to wash it away.

It's like when you're playing hide and seek, and suddenly someone sneezes right in your face, you blink and laugh!