Succinic acid, an intermediate in the metabolism of food molecules, has a molecular weight of 118.1. When 1.926 g of succinic acid was dissolved in water and titrated, 65.20 mL of 0.5000 M NaOH solution was required to neutralize the acid. How many acidic hydrogens are there in a mol-ecule of succinic acid? (LO 4.16) (a) 1 (b) 2 (c) 3 (d) 4

Video transcript

Hello. Everyone in this video, we want to determine the number of city hydrogen in our lactic acid. So first thing we're gonna do is to go ahead and compare the moles of lactic acid versus the moles of hydrogen from arbitration reaction. So we're given the problem that we have a 6.50 g sample of lactic acid. We just want to go ahead and convert our grams of lactic acid into moles. How we can do this is by using the molar mass of lactic acid. So we can see that. It's 90 9.078 g of lactic acid For every one moon of lactic acid. All right, we can see that the units of g will go ahead and cancel leaving us with the moles of lactic acid. So once you put these values into the calculator, we can see that it comes out to be 0.07216 of course units being moles of lactic acid. Not to compare it with the moles of hydrogen. We'll go ahead and use any O. H. Starting off with the calculations were given that it was being tight treated with 19.20 million years of Noh Will convert the Millimeter units into leaders to utilize our concentration here. So for every 1000 ml we have one leader. Then we can see the middle layers will cancel. Then we can go ahead and use our concentration here as a conversion factor. So for every one liter of solution we have 0.800 moles of N.A. O. H. Now, lastly, we want the moles of our hydrogen. So we can see here that in our molecule that everything is a 1- ratio. So we can say that for every one mole of N.A. O. H., We have one mole of Rh plus Canyon. Again, you can see now that theaters were canceled and moles of NH were canceled. So putting all these values into the calculator, I get the value of 0. moles of H plus. So now coincidentally you can see that these two values are actually the same. So what they have a 1 to 1 ratio of lactic acid to R H plus cans. So we can say or conclude that lactic acid has one acidic Hydrogen. Again, it's because we have a 1-1 ratio. So this is going to be my final answer for this problem.