Parts per Million (ppm)

here. We're going to say that extremely dilute solution concentrations are expressed in parts per million, abbreviated as ppm or parts per billion, or bring it as ppb. Now we're going to say here units can either be in mass or volume when it comes to ppm or ppb. Now, let's take a look at parts per million. We're gonna say this represents the number of parts either in grams or milliliters per one million parts. And remember, one million is 10 to the sixth in a quick solution. Helpful thing to help to help you with parts per million is that one parts per million is equivalent to one mg per one leader. So here we take a look at parts per million. We can look at it, look at it and neither are form of mass or in a form of volume. If we're looking at parts per million in terms of mass, we're gonna say it equals grams of solute divided by grams of solution times 10 to the six. And if we're looking at parts per million in terms of volume, then it becomes milliliters of solute divided by milliliters of solution times 10 to the six. So this setup should be kind of reminiscent of mass percent where it be grams over grams times 100%. Now, instead of doing 100% we're now dealing with 10 to the six because we're dealing with a million parts, one million parts. All right, so just keep in mind, we deal with PPM and later on ppb when discussing very extremely diluted concentrations.

What is the concentration in parts per million of D. D. T. A non biodegradable pesticide in two mg in one kg needle fish tissue? All right, so we want parts per million. So that's going to equal the grams of our salute, divided by grants of solution Times 10 to the six. We have an issue, though these units are not. Ingram's ones and milligrams once in kilograms convert them both to Graham's first. So we have two mg. I remember one mg when Millie is 10 to the negative three. So that's 2.0 times 10 to the -3 gramps And then remember, one kg is equivalent to 1000 g. So we take that and plug it in. So we have 2.0 times 10 to the negative three g divided by 1000 g Times 10 to the six. When we do that, we get back to 0.0 ppm, so that will be our parts per million of DDT. For this particular example, question

ppb, otherwise known as parts per billion, represents the number of parts either in grams or milliliters per one billion parts. And remember, one billion is 10 to the nine now, when in aqueous solutions, just remember that we can make the connection that one ppb equals one microgram per one leader. Now, when dealing with parts per billion in terms of mass, we're gonna say it's equal two g of solute divided by grams of solution times 10 to the nine. And when looking at parts per billion in terms of volume, it then becomes milliliters of solution divided by millimeters or millions of solute divided by milliliters of solution times 10 to the nine. So just keep in mind when dealing with parts per billion and a quick solution. There's this connection and also the difference between parts per billion when dealing with Mass and when dealing with volume

A 2.4 L sample of an adequate solution contains . ml of ammonia. What is the concentration of ammonia in the solution expressed as parts per billion? Alright. Since we're dealing with volume here, that must mean we're dealing with parts per billion in terms of volume. So we'd say here parts per billion would equal the middle leaders of our salute divided by mil leaders of our solution, which in this case is our sample times turn to the night. Here we plug in .012 middle leaders of our ammonia, which is our salute Divided by now we need to convert leaders in two ml and remember that for every one milli, it's 10 to the negative three leaders. So here that comes out to 2400 ml, which is what we're going to place over here And then times 10 to the 9th. When we do that, that's going to give me as an answer. 5000 parts per billion And out of the choices shown options often be would be the correct answer. So be 5000 parts per billion will be the correct concentration of NH three, expressed in parts per billion