conversions for biochem

Question

how many grams of CaBr2 solid do i need to make 600ml of 4% CaBr2 solution

Answer 1

Hey Emily,

Great question. Let's start by breaking down the information given in the question. In order to find the grams of CaBr2 needed, we have to start with the solution. It tells us that it is 4% CaBr2 solution. When it tells us a solution in percentage and no other information, we can generally assume that it is weight/volume percentage. Sometimes, it can be volume/volume or weight/weight. In this case, it is most likely referring to weight/volume. Therefore, we can break it down like this:

4% = grams CaBr2 (weight) / 100ml solution(volume) = 4g CaBr2 / 100ml solution. Therefore, we need 4g of CaBr2 for every 100ml of solution.

Lastly, we need to use this ratio to figure out how much CaBr2 we need to make 600ml of the solution:

(4g CaBr2 / 100ml solution) x (600ml) = 24g CaBr2.

I hope this is helpful! Let me know if you need any further explanation.