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look at the two thermometers below identify which is Celsius and which is Fahrenheit and then label the boiling and freezing points of water on each now the Celsius scale is what's used in most of the world so the Celsius scale Celsius Celsius is most of the world most of the world and the easy way to tell that you're dealing with the Celsius scales on the cents on the Celsius scale zero zero degrees is freezing of water freezing it of water at standard temperature and pressure and 100 degrees is the boiling point the boiling point of water at standard temperature and pressure now on the Fahrenheit scale Fahrenheit which is used mainly in the United States Fahrenheit scale the freezing point of water is 32 degrees 32 degrees is freezing 32 degrees is freezing and boiling of water is 212 degrees boiling of water is 212 degrees as you could tell Celsius the whole scale came from using freezing as zero of regular water at standard temperature and pressure and setting a hundred to be boiling and so on some level makes a little bit more logical sense but at least here in the US we still use Fahrenheit now let's figure out which of these are Fahrenheit and which are Celsius now remember regardless of which thermometer you're using water will always actually boil at the exact same temperature so Fahrenheit 32 degrees this has to be the same thing as Celsius zero degrees so let's see what happens so when this temperature right here is zero this one over here looks like it's negative something so this one right here doesn't look like Celsius here if we say this is Celsius this looks pretty close to 32 on this one so this one right here looks like let me do that in a darker color so this one right here looks like Celsius Celsius and this one right here looks like Fahrenheit Fahrenheit and the way I was able to tell is that the zero degree Celsius needs to be the same thing as 32 degrees Fahrenheit that in both cases this is where this right here is where water freezes the freezing point that is water freezing and let's make sure we're right so this is a Celsius scale this is where water will boil 100 degrees Celsius and that looks like it is right about 212 on the other scale so right there is where water is boiling water is boiling at standard temperature and pressure so this thing on the right right here I guess I'll circle it in an orange that is that is Celsius and then the one on the left I'll do it in magenta the one on the left is Fahrenheit