The ball-and-stick molecular model is a representation of caf-feine. Calculate the molecular weight of caffeine. (Gray = C, red = O, blue = N, ivory = H.) (LO 3.3)

(a) 194.2 (b) 182.2 (c) 192.2 (d) 180.2

Video transcript

Hey everyone, we're told that the ball and stick model shown below is for uric acid, a component of urine determined the molar mass of uric acid and were provided a legend. To answer this question, we first need to determine the formula of uric acid. So looking at our ball and stick model, we can see that we have 12345 and we have five of carbon. Looking at our hydrogen, we can see that we have four of hydrogen, 123 and four. Next looking at nitrogen, we can see that we have 123 and four. Now looking at our oxygen, we can see we have 12 and three. So our final formula is going to be C five H four N 403. And this is the formula for uric acid. Now we can go ahead and determine our molar mass to determine our molar mass. We're going to take Each element and break it down. So starting with carbon, we see we have five of carbon. Now we're going to multiply this by smaller mass of 12. g per mole. Which can be found in our periodic table. Now looking at hydrogen, we have four of hydrogen and now we're going to multiply this by 1.794 g per mole. Which is again, it's Mueller mass. Now looking at nitrogen, we have four of nitrogen and we're going to multiply this by 14.00674 g per mole. And lastly looking at oxygen, we have three of oxygen. Now we're going to multiply this by smaller mass of 15. g per mole. Now, once we multiply each of these elements and calculate their values, we're going to add each of them up, And this gives us a molar mass of 168.1104 g per mole for our uric acid. Now, I hope that made sense and let us know if you have any questions.