Law of Definite Proportions

by Jules Bruno
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Let's examine the law definite proportions. In 17 99 the French chemist Joseph L. Promised originated the law of definite proportions because of its immense contributions to it. It's sometimes referred to simply ask Proust law, but it also goes by the law of constant or definite composition. The law itself uses what we call mass ratios. These mass ratios are fractions or proportions of elements by Mass. The whole concept behind a lot of definite proportions is that different samples of a cure chemical compound always contained the same proportion development by mass. So let's say, for example, that I take ah sample from New York City, and I suspect that it's CO two and I take a sample of in another city, London, England. And I suspect that CO two, if we're following the law of different proportions, both samples should have the same mass ratio. Now, for the mass ratio, we're gonna place the element with the larger mass on top, not going back to our whole idea of co two in two different cities. Remember, Seal to itself is composed of one carbon and two oxygen, and we know that if we look at the periodic table. The atomic massive carbon is 12.1 g per mole in the massive, oxygen is around 16 g per mole. When you multiply the number of each element by atomic Mass, we'll see how much of it contributes to the old raw mass of CO. Two. So carbon itself contributes 12.1 g total, and oxygen contributes 32 g total. Not using the mass ratio, we place the larger mass on top, which is the 32 g of oxygen in the smaller mass on the bottom. When we divide those two numbers, that gives me approximately 2 66. What that 2.66 is telling me is that we have 2. oxygen for everyone. Carbon. This would be our mass ratio. And if our examining two samples of CO. 21 from New York City and one from London if they both were indeed co. Two, they both should give me back the same exact mass ratio. That's what the law of definite proportion hinges on. If we know the mass ratio of a given sample and we're examining it against the unknown sample, I use this law to determine if they're the same sample. Alright, now we get the idea behind the law of definite proportions. So let's move on. Let's talk about calculations and different types of problems associated with the law of definite proportions.