So in this video I'll be covering the last property of water which is the thermal property of water. In my previous videos, I made a few videos, I talked about the solvent property of water as you can see here, I talked about adhesion and cohesion properties of water and then I also talked about hydrogen bonding but if you haven't watched any of these videos make sure to at least check out my video on hydrogen bonding because that's the crucial thing that you need to know you need to understand this because because um hydrogen bonding in water if you can understand why it happens hydrogen bonding is the main reason for why any of its properties are possible so at least check out that one make sure you understand it and then then watch this video or any of my other ones so thermal property of water so we have a glass of water here okay all of these are water molecules They're arranged and they're doing hydrogen bonding with each other, which I explained in the first video. Hydrogen bonding is a relatively strong bond that can keep these water molecules together, which is why it's liquid, because pretend these were not here, then these molecules would just float away and we'd be gas.
So thank God to hydrogen bonds, you can have a liquid water and you can drink that. So what if, I have a question for you, so what if the sun comes out? What normally happens if there's... Warm day when you have a pool a big pool Do you notice this one have you ever noticed that even though it's extremely warm the pool temperature doesn't really change It like remains pretty constant some days It'd be really warm and you'd actually go into the pool and you'd be like surprised at how cold it is and that is That experience right there that which what you're noticing is one of the proper thermal properties of water It's the fact that water takes such a long time to change temperature no matter how much heat you're putting, it will take so long to change temperature. And the reason and part reason for that is because of this hydrogen bonding.
The sun, it needs to supply so much more heat to break these hydrogen bonds to change their to change the temperature of the water than for most other molecules. Because most other molecules don't have this hydrogen bond and this hydrogen bond causes the causes water to need more temperature or more heat to be able to change to change its temperature. Okay, I hope you understood that. And to actually, and you probably know this, but so what you actually need is 100 degrees Celsius before water will actually start evaporating or boiling, you know. You need so much heat before this will start evaporating and losing its water molecules.
Say it's 100 degrees, now these hydrogen bonds, which I'll show here, will start breaking. because the temperatures are really high. And once they start breaking, these water molecules will just now they now they'll be gaseous right so now they'll leave and slowly the cup will get empty. And that's what you might notice if you have a cup outside or a pool.
If you know a pool somewhere, you'll notice that as summer goes on by the end of summer if no one refills the pool it will just be empty. And that's because high temperatures slowly cause the breaking of these bonds. they would start leaving.
But it's still amazing how long it takes for water to heat up and start to empty up because most molecules that happens at a very low temperature so that's why water is so special because imagine water would start boiling at like 10 degrees celsius then nothing would be possible on earth you wouldn't be able to drink water because it'd be gassed all the time and your blood in your body wouldn't be able to be liquid it'd be gaseous which means none of the reactions in your body can take place so it's so important that water has this high specific heat capacity. So what you call this, I forgot to mention, it has a high specific heat capacity. High specific heat just means it takes a lot of temperature before it changes, I mean it takes a lot of heat before it changes its temperature. And like I said that's so important in your body because if your blood were to be gas so quickly then none of the reactions would be possible.
And that's not only important in your body but important in the whole world. Because since most of the earth is water, if water was not so, if water didn't have this ability, this high specific heat, then none of the reactions would be able to happen. So this is the one example of one of the thermal heat properties.
The other ones are very similar. So another one, oh yeah, by the way, so if you have methane, methane, I mentioned earlier, you should know for the IB because it basically has the exact opposite properties of what water has. It is not polar, water is polar and that's why it can do hydrogen bonding. because these positive hydrogens check out my video on this by the way so you can understand understand this because the hydrogen is positive and it will bind to the negative oxygen so positive and negative charges attract therefore they bind and form this hydrogen bond but that doesn't happen in methane and if you understand why it doesn't happen check out that video and it will be clear but basically methane can't do hydrogen bonding which means it's it doesn't have a high specific heat capacity so as soon as the sun comes out or even at negative 161 degrees celsius That's extremely low. At this temperature, methane is already a gas.
It's already boiling at this temperature, and that's freezing. That just shows that water is really special, because being able to still be liquid at such high temperatures is amazing. And that's why the Earth is actually possible to exist.
So just remember methane doesn't have hydrogen bonding, and that means a low specific heat. It was basically a gas at such low temperatures. Now, Two other properties arise from this diagram.
So you know, water, so first of all, water has a high specific heat. Second of all, water is an extremely good coolant. So, like, think about it.
When you go running, right, you get extremely warm and you start sweating. That, everyone knows that. But this is actually, without you knowing it, one of the properties of water.
One of the thermal properties of water. Because water takes such a long time, it needs to absorb so much heat before it will evaporate. So because it needs so much heat before it evaporates, then you can think of your body.
Your body generates heat, right? Because inside a lot of things are happening. When you're running, you're doing exercise, you're getting warm inside. And all that heat inside your body is now going into breaking these...
Because your body is so much water, 70% water. So all that heat that is created by exercising in your body will now go into breaking these bonds. Because now it's a high temperature.
And when these bonds are broken, these water molecules will leave. They will evaporate. But they will evaporate with the heat that your body put into making the bonds break. That means when they evaporate, they take that heat that your body gave with it.
And that cools you down because now heat was taken out of your body. Okay, so that's one of the other properties. And I'll show you here. Water can also act as a coolant because when we sweat, the water from our body evaporates.
And then it takes a lot of energy with it. The energy from your body that was used to break those hydrogen bonds. and that cools down your body.
And the last one that I mentioned that I kind of already mentioned was because water is liquid at room to room at like range of temperatures a large range of temperatures we know it's liquid from zero to 100 right that's extremely big because we know the earth ranges about between really cold and really warm but between most temperatures on earth most places are between like negative 20 and then 100 so at most of the temperatures water is liquid and that's really good because then reactions can pretty much happen anywhere on earth so if you can remember these basic this diagram and basically why water is so good in terms of its thermal property by the way if you don't know what thermal means it just means heat it's a science word for heat so it's heat property um if you can remember this that's great that's all you need to know i cover all the detail that you need to know for the ib so um nothing else that you should need to research so just know this and you'll be good in my next video i'll go over some As you can see here, some IB questions that are relevant to all the things I talked about with water, including hydrogen bonding, thermal property, solvent property, cohesion, and adhesion. So if you want some IB questions that are explained, just check out my next video.