Question #82dbf
2 Answers
Explanation:
Parts per million, or ppm, is simply another way of expression the concentration of a solution.
More specifically, parts per million can be used for solutions that contain very, very small amounts, often called trace amounts, of solutes.
By definition, ppm concentration is expressed as
#color(blue)(|bar(ul(color(white)(a/)"ppm" = "grams of solute"/"grams of solvent" xx 10^6color(white)(a/a)|)))#
In essence, a concentration of
#"1 ppm" = (1color(red)(cancel(color(black)("g"))) "solute")/(color(brown)(cancel(color(black)(10^6)))color(red)(cancel(color(black)("g")))"solvent") xx color(brown)(cancel(color(black)(10^6)))#
In your case, the solution is said to have a concentration of
Notice that if you were to pick a sample of
#"73.2 g solute " + color(white)(a)10^6"g solvent" ~~ 10^6"g solution"#
Now, to get the solution's percent concentration by mass (or weight percent),
#color(blue)(|bar(ul(color(white)(a/a)"% m/m" = "grams of solute"/"grams of solution" xx 10^2color(white)(a/a)|)))#
Since we've picked a sample that contains
#"% m/m" = (73.2 color(red)(cancel(color(black)("g"))))/(10^6color(red)(cancel(color(black)("g")))) xx 10^2 = color(green)(|bar(ul(color(white)(a/a)"0.00732%"color(white)(a/a)|)))#
So, instead of saying that your solution is
Ppm stands for "parts per million".
Explanation:
In other words, "How many grams are in one million grams of the sample?"
In the same way, mass percent is the number of grams in 100 g of the sample.
For example,
We want to know the mass of the component in