ELI5: Explain Like I'm 5

Mercury(II) oxide

Okay kiddo, have you ever heard of the element mercury? It's a metal that's sometimes used in things like thermometers or light bulbs. Now, when mercury combines with oxygen, it becomes something called mercury(ii) oxide.

Mercury(ii) oxide looks like a reddish-brown powder. It's made up of tiny particles called molecules that stick together to form a solid. Molecules are like really small Lego blocks that can join together to make bigger structures.

Now, here's the cool part. When mercury(ii) oxide is heated up, it can actually break apart into its two separate elements: mercury and oxygen. This is because when things get hot, their molecules start moving really fast and can break away from each other.

So, let's say you take some mercury(ii) oxide and heat it up. You'll see it turn into a shiny liquid mercury and a gas called oxygen. That's pretty amazing, right?

However, it's important to remember that mercury is a toxic substance, which means it can be harmful to living things like plants and animals, including people. So, we need to be careful when working with or around mercury(ii) oxide to make sure we don't get sick.