Now the oxidation number is an important idea as we make our way towards oxidation and reduction reactions, otherwise known as redox reactions. Now, first, we're gonna say that the oxidation number itself is an elements ability to gain, lose or share electrons when alone or in a compound. And we're gonna say when it comes to oxidation numbers, it's important to talk about the natural state of an element now for Adam in its natural state. Also called It's Standard State. It's oxidation number or oxidation. State is equal to zero. Now remember, we have our periodic table here. We know that with our periodic table there are charges that are unique to different groups, and we know that certain elements exist in certain forms in nature. Now, when it comes to Group One A. We know that the charges plus one group too, is plus two three years plus three. Anyway, we tend to foray. We tend to skip because some elements have varying positive charges. So we're just gonna skip that. We know that Group five a is minus three, minus two minus one. And remember, everything is trying to become a noble gas. They're perfect. So they tend not to have charges. If you don't remember this or you haven't seen my videos on it and you want to explore this a little bit further, make sure you take a look at my videos on periodic table charges. Now, also, remember, we've talked about natural states of elements in the past as well. So when it comes to elements of the periodic table, we have our die atomic molecules. Those are hydrogen, which is H two nitrogen, oxygen flooring, chlorine bro. Mean and, of course, our ideye. Also remember that phosphorus tends to exist as P four in its natural state when found in nature, and that sulfur is s eight. And since selenium is right below sulfur, it is s e eight. These are the natural forms of these different elements when they're found in nature and remember all the others. I'm not writing them in because in nature they exist as mono atomic atoms. This you can also remember refresh your memory by taking a look at my periodic table videos. We talk about the natural state of elements, but right now, just realize that if you find an atom in its elemental state or natural state of Standard State. Whatever term you're most comfortable with, its oxidation number will be equal to zero.