Hello everyone. As you all remember, we took a pretty test on chemistry, which is our next student. So first of all, I have with the basic chemistry which are colleagues. You have probably, most definitely, have heard about that in the first. And one thing I have not noticed are these elements are pure substances. You're not there absolutely, like hydrogen, it's just hydrogen, nothing else, and it's unincorporated. From before I continue, I'd like to make a clear definition between atom and element, definitely gives both any confusion. And atom is made up of proteins, which have a positive charge, and you charge the chemical, chemical, chemical, and chemical, which are both eliminated in clear and electrophilic charge, which have negative charge. And then it is made up of atoms of the same structure, like hydrogen. Hydrogen is only made up of atoms that have one protein and one electron. So that idea of this information, I'll give you some extra facts, because knowledge is power. Did you carbon what I did there? I dig this. Throughout those years, there are many combinations of these elements, which you see and use every single day. And there are two different types of these combinations. They're compounds and mixtures. First, we'll talk about compounds. Compounds are combinations of elements that are only made chemically. And they're not made up of at least two elements, and those two plus elements can be in synonyms, like hydrogen, H2, oxygen, and T. And some compounds that we typically see in mi are a lot of H2O, table salt, NACL, or 131 chlorine table strider, C12, H22O11, or 12 carbons, 22 hydrogen, 11 oxins, and CHOP. There's one calcium, one carbon, and four oxidins, so CACO30. And since these compounds are one chemically, they can only be destroyed or broken down chemically. So now that universe, we'll move on to mixtures. Mixtures are the combinations that are made physically, rather than chemically like compounds. And there are two different types of mixtures that can be pronounced heterogeneous, or heterogeneous, or genus. And those type of mixtures are mixtures that are mixed to look separate. Like if you mix salt and pepper, you can see that it's different things in that mixture. And then there's homogenous mixtures, or homogenous mixtures, and they're also called solutions. And one of them today don't look separate, like air. You can't see the nitrogen or the oxygen in it. So it's like the nature of a liberal learning journey with me today. But it seems like I have to H2O, so carbony or NL later.