What is the molarity of a solution of K2CO3 prepared by dissolving 7.77 g of K2CO3 in enough water to make 272.89 mL of solution?

Answer 1

Hey Ke'Asia! Let's work this one out. We know that Molarity is equal to Moles of Solute / Liters of Solution. To start this problem, let's find how many moles of K₂CO₃ are in 7.77 g. We first need to find the molar mass of K₂CO₃ which is 138.204 g/mol. Now all we need to do is divide 7.77 by 138.204. This will let us know how many moles of K₂CO₃ we are working with. You should get 0.05622124 moles of K₂CO₃. Now that we know the moles of Solute, we need the Liters of Solution. This one is super easy. We take 272.89 and divide it by 1000. This is because we want Liters of solutions, not mL of solutions. We are given the solution is mL, so to convert from mL to Liters, we divide by 1000 because there are 1000 mL in one Liter. You should end up with 0.27289 Liters. Now, let's put it all together!

0.05622124 moles / 0.27289 Liters = 0.20602162

The molarity of the solution prepared is 0.20602162.

Hope this helps!!!