This video, we're gonna go over question 136 from Chapter four, which says in the spectroscopic analysis of many substances, a series of standard solutions of known concentration are measured to generate a calibration curve. How would you prepare standard solutions containing 10 25 50 75 in 100 parts per 1,000,000 of copper from a comfort from a commercially produced 1000 parts per 1,000,000 solution? Assume each solution has a final volume of 100 no leaders. Um, so basically, we need to do a series of dilutions to get these more dilute. 10 25 50 75 1 100 parts per 1,000,000 solutions from this more concentrated 1000 parts per 1,000,000 solution. Um, so once we do these delusions, you can measure whatever property you need thio about these from these solutions so that you can determine the concentration of an unknown solution based on where it falls on your calibration curve. Let's go ahead and do our delusions. So if we want a solution, we want 100 milliliters of a 10 part per 1,000,000 10.0 part per 1,000,000 solution on from 1000 parts per 1,000,000. Then we're going to need to do a dilution we're going to use C one V one equals C to be too where c wouldn't be one are the concentration and volume of the more concentrated solution that you're diluting and then see to envy To are your desired concentration at the end of your dilution and the volume of your solution that you're making eso In this case, C one is 1000 parts per 1,000,000. V one is actually our unknown. We want to know what volume of our 1000 parts 1,000,000 solution we need in order. Thio, in order to make this 100 leaders of 10 parts per 1,000,000 solution S O C two is our tens parts per 1,000,000 and V two is our 100 no leaders. So if I sold this for B one, what I get is one millimeter 1.0 millilitres. I'm so in order to make the solution, you would take 10 take one mil leader of the 1000 parts per 1,000,000 solution on, then add enough water to equal 100 old leaders Next we want, um 25 ppm. So again we have C one V one is equal to see to be too. Um and now see, one is still our 1000 ppm solution. Everyone is a gun are unknown. C two is now 25.0 ppm and V two is our 100 milliliters s o. We solve this for viewing. What we get is 2.50 millilitres. So we would, uh we would measure out 2.50 millilitres of the 1000 parts per 1,000,000 million solution on then out enough water to equal 100 milliliters s o the next. A solution we want to make is a 50 parts per 1,000,000 solution. So again see won we won is equal to see to be too C one is 1000 ppl. The one is our unknown. C two is 50 ppm and V two is our 100 milliliters. It's how much of our solution we want to make s o. We saw this for view one. What we get is 5.0 millilitres. So we would measure out five milliliters of the 1000 parts per 1,000,000 solution on and then add enough water to equal 100 milliliters. So next we have 75 ppm. So again, C one everyone is equal to see to V two. C one is our 1000 ppm. V one is our unknown. C two is 75 ppm and V two is 100 milliliters. Eso we solve this for everyone and what we get is 7.5 zero milliliters Noticed that since I gave this volume in milliliters the volume I get is my answers and the leaders eso again. We would measure out 7.50 millilitres of the 1000 parts per 1,000,000 solution and then add enough water to equal 100 milliliters. Finally, the last solution we want to make is the 100 Um, the 100 ppm solution. Um so again, C one V one is equal to see to you too. C one is 1000 ppm. Be one is the unknown. C two is 100 ppm and V two is 100 milliliters. So we saw this for everyone and what we get is 10 milliliters. So you would measure out 10 milliliters of the 1000 parts per 1,000,000 solution and then add enough water to dilute it to 100 milliliters.