1) GOLDEN TIP - in any numerical question, I recommend using a spreadsheet so that if you change a number it automatically updates the answer - have one column with your numbers and calculations in and then the column next to it as your units so that you can see what you've done and where you need to go next
2) look at the axes and see if you can input any info given to you into one axis to read off something from the other 3) don't get confused by the ppm => 1 ppm = 1 mg/dm^3 4) you are given it's name so you can find out it's Mr 5) i didn't actually use the density (as i used the Mr instead)
1) GOLDEN TIP - in any numerical question, I recommend using a spreadsheet so that if you change a number it automatically updates the answer - have one column with your numbers and calculations in and then the column next to it as your units so that you can see what you've done and where you need to go next
2) look at the axes and see if you can input any info given to you into one axis to read off something from the other 3) don't get confused by the ppm => 1 ppm = 1 mg/dm^3 4) you are given it's name so you can find out it's Mr 5) i didn't actually use the density (as i used the Mr instead)
hope this helps
thanks, and the density confused me loads cause i didnt know where to use it. ill have another go now
Sorry I misread >.<, so I end up with 31622 ppm. How do I find the volume and moles with two densitys' ?
i didnt use the density at all. you know the compound so you know the mr of the compound. so you mess aroiund with the numbers to change mg/dm3 to mol/dm-3