ELI5: Explain Like I'm 5

Molecular autoionization

So, you know that everything is made up of teeny-tiny things called atoms, right? Well, sometimes these atoms get together and make even bigger things called molecules. Now, some molecules are really good at holding onto all their electrons and staying neutral (having the same amount of positive and negative charges). But other molecules, like some gases and liquids, can lose or gain one or more electrons really easily. When this happens, the molecule becomes either positively or negatively charged, like a little battery.

Now, sometimes these charged molecules can get really excited and start shaking and moving around a lot. And when they do this, they can sometimes bump into other molecules and knock an electron right off of them! This is called autoionization because the molecule is ionizing (becoming a charged ion) all by itself because of its own movement and energy.

One example of this is when water molecules in the air get excited by sunlight or other sources of energy. They can bump into other water molecules and knock an electron off, becoming positively charged ions (H+) and negatively charged ions (OH-). This is actually how lightning is created! When enough of these charged ions build up in the clouds, they can create huge electrical sparks that we see as lightning bolts.

So, in summary, molecular autoionization is when a molecule becomes a charged ion all by itself because of its own energy and movement, and this can happen when the molecule gets really excited and bumps into other molecules. It's like a little dancing battery!
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