This question is asking us to determine how many grams of sodium di hydrogen, phosphate and di sodium hydrogen phosphate we need to prepare one leader of phosphate cover at Ph. Seven. So I have written the molecular weight of the two species involved, and, um as pH increases, uh, sodium Hydrogen phosphate is deep protein ated into di sodium hydrogen phosphate, and I have just written the desired pH and the P K a, um, of these species for the sake of ease. So the first thing we need to do is determine how much of the acid and the conjugate base are present in the solution. The question has told us that the total concentration of phosphate is, uh, 0.1 Mueller, which is basically the some of the acid and the conjugate base. Um, so we will just arbitrarily define what these are. So I will say the acid is X and the that makes the conjugate base 0.1 minus X. We will use the Henderson Hasselbach equation, which is a very useful equation and chemistry, too. Um, figure out these concentrations, so yeah, we already know the pH. Oh, I wrote the Ph wrong earlier. That is my bad. PH should be, uh, seven point, though, So we know the pH. It is seven. Uh, we know the PKK, which is 7.2, and we are trying to find the ratio, and we have previously defined are contacted base as 0.1 minus X and our acid Aztecs. The first step in rearranging this equation is subtracting 7.2 from seven, which is negative 0.2. And the inverse of log is taking 10 to the power of what we had on our other side, which is, I believe, 0.631 and we set that equal to zero point one minus X over X and 631 times X equals 0.1 minus x. So we're just gonna group, um, the terms with X on one side, giving us 1.631 X equals 0.1. And then when we divide by 1.631 on both sides, we get X equals zero point on 06 to Mueller, which is our concentration of acid as we defined X earlier on. So our concentration of the conjugate base as we have previously defined is 0.1 minus X, which we now know is 0.62 which equals 0.38 Mueller. So just to write that in terms that make it easier to think about our phosphate buffer, uh, this is our acid equals H A equals 0.6 to Mueller and our conjugate piece. Oops. Let's try that again. Our contact of based di sodium hydrogen phosphate aged one. Yeah. Star contacted Base. Awesome. Now that we know the concentrations, we can get into the math. So as we know, polarity is moles divided by volume and leaders. So when we have 0.6 to Mueller, we really have 0.62 moles. Her leader and these are calculations for our acid. So we're gonna do some study geometry. Um, if you remember previously ah, we were given the molecular weight in the question and the molecular weight of sodium di hydrogen phosphate is 100 and 38 g per remote. So, um, this is basically how you do start geometry. You try to have the units equivalent across, and, um, we know that one mole is 138 g. I hope you know how to do strike geometry and we basically multiply everything along the top, multiply everything along the bottom and then divide the tube. So once we do that, we end up with 8.56 g of sodium dire hydrogen phosphate. And basically what this times H 20 means is that it's a hydrate. Now we do the same thing for our conjugate base. Mhm 0.38 moles per liter and then one mole was 142 g as per the molecular weight. And then when we follow the same procedure, we end up with 5.34 g of di sodium hydrogen phosphate hydrate. So this is our answer right here. I wasn't the prettiest, but yep, that's basically it. And thank you for joining me for this video. I hope my process made sense