 Let's explore how metals react with oxygen. To do that, let's do a couple of experiments. We'll first take a small ribbon of magnesium and burn it and see what happens. Oh, it burns very nicely. And we get this white powder. So what's going on? This time we're gonna take a few copper ribbons and we're gonna heat it. And let's see what's gonna happen. And you see, it turned brown. So we notice that magnesium, when you burnt it, it became white powder. What's going on? What happened over there? Well, it turns out that when we burnt magnesium, it reacted with the oxygen in the atmosphere to give you magnesium oxide. And now this equation is not really balanced. So to balance this, I need to put two here and then I have to put two here, so there you go. Now similarly, when copper was heated, it starts reacting with the oxygen in the atmosphere. And again, what we now get is copper oxide or cuprous oxide. Similarly, if you take sodium, there's a reason why sodium is always stored in kerosene. Because if you take sodium out, then you don't even have to heat it. It will react with the oxygen to give you sodium oxide. Now because sodium oxide has Na2O, the balancing you'll have to put four Na over here to balance everything out. So in general, what happens when you react, what do you get when metals react with oxygen? Well, metals react with oxygen to give you metal oxide. But the thing that you do understand is that not all the metals are equally reactive. For example, sodium and even potassium for that matter, they are so reactive that if you just expose them to air, they will react. And that's why we store, for example, sodium in kerosene. Copper, well, you have to heat it. Magnesium also you have to heat it, but you can see that magnesium burns much more vigorously compared to copper. And so they have different reactivities. But what about certain metals like gold and silver? We call them the noble metals because they have such low reactivity that they almost don't react with oxygen at all. So in general, metals do react with oxygen to give you metal oxide, but different metals have different reactivities. Some will react directly, some won't react at all. And for some other metals, you'll have to heat them for them to react.