ppm (2 Viewers)

[Premus]

Hey

here's a question from the 2001 catholic trial q14

A chemist has a solution containing 180 ppm of phosphate ions. He takes 10mL of this solution , and adds 90mL of distilled water to it. the phosphate ion concentration in this 100mL solution is:
a) 18 ppm
b) 20 ppm
c) 160 ppm
d) 200 ppm

is it just a 10 X dilution....so would it be 18ppm ?

Thanks!

 

[Tommy_Lamp]

I think thats right.

 

[maatsby]

yeh u can check it out using C1V1 = C2V2

180 * 10 = C2 * 100
1800/100 = C2

which equals 18ppm