I have no idea what I'm doing wrong here...
Question: A solution is 0.3% by mass calcium chloride. Therefore, 145 g of the solution contains how many grams of calcium chloride?
My solution:
145g x (0.3g / 100g) = 0.435g
or 0.44g CaCl2
What am I doing wrong? Thank you!
see below
In order to solve this problem, you need to understand that the given concentration of the solution (0.3% by mass) represents the mass of calcium chloride (CaCl2) in 100 g of the solution.
To find out how many grams of calcium chloride are in 145 g of the solution, you can set up a proportion:
0.3 g CaCl2 --> 100 g solution
x g CaCl2 --> 145 g solution
To solve the proportion, you can cross-multiply and then divide:
x = (0.3 g CaCl2 * 145 g solution)/100 g solution
x = 0.435 g CaCl2
So, your initial calculation was correct. The mass of calcium chloride in 145 g of the solution is indeed 0.435 g or approximately 0.44 g CaCl2.
Therefore, it seems that you didn't make any mistakes in your calculation. Your answer of 0.44 g CaCl2 is correct based on the given information.