1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Concentration Problem

  1. Sep 29, 2010 #1
    1. The problem statement, all variables and given/known data
    Suppose the concentration of phosphate in Phoenix tap water is 7.3 ppm (mass based), then what is the concentration of selenium in milligrams per liter? The density of water is 1 g/mL.

    2. Relevant equations

    Phosphate: PO4-3; 7.3 parts/million

    3. The attempt at a solution
    I honestly have no idea how to start. They want concentration of selenium but there is no mention of it from the information stem. Maybe it's just a typo and they mean concentration of phosphate in mg/L. Anyways, please guide me in the right direction. Thanks!
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Sep 29, 2010 #2


    User Avatar

    Staff: Mentor

    There is some piece of information missing, no way this can be solved as worded.

    Well, there is a slight chance that there was some additional information buried in the text outside of the question, stating that ratio of both in typical drinking water is almost constant or something like that. But I don't think that's the case.

  4. Oct 1, 2010 #3
    Yeah... it was a typo by the professor. Haha. Thanks anyways though!
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Threads - Concentration Problem Date
Mass of ammonia through nitrate concentration problem Jun 11, 2017
Easy Stoichiometry Concentration Problem Jan 5, 2016
Concentration Problem Jan 19, 2015