[JoshL]

I've just started Solubility and Dilutions in Chem 20 and I'm kind of struggling to grasp the information. I'm mostly having trouble with C1 V1 C2 V2 and determining PPM.I'm also having a little bit of trouble figuring out concentration equations and molarity. I have a few sample questions that I'm having trouble with and it would be much appreciated if someone could explain them to me. We have just started this unit but i would like to understand it well enough for upcoming tests.  Thanks in advance!

1) A student needs to make 650 mL of a sodium phosphate solution with a concentration of 2.45mol/L
a) what mass of sodium phosphate does the student need to weigh out?
b) what will the concentration of each ion be?

2) Mercury Bio-accumulates in polar bears. what mass of mercury is present in a 30 kg sample of polar bear meat if the concentration is 16 ppm

3) A researcher needs 250 mL of a solution with a NO3- concentration of 1.5 M. what mass of aluminum nitrate must she weigh out to make this solution?

[Borek]

You have to show your attempts at solving the question to receive help. This is a forum policy.

1) A student needs to make 650 mL of a sodium phosphate solution with a concentration of 2.45mol/L

How many moles is that?