On the jan 2011 paper I'm confused with question 5(b). How do you calculate the volumes? Many thanks in advance
AQA unit 1 biology past paper Q Watch
- Thread Starter
- 04-01-2013 19:06
- 04-01-2013 19:52
The solution is 1.0 mol dm3 i.e. is ALL (100%) sodium chloride. The solution needs to be 0.2 mol (20%) dm3 of sodium chloride.
The total solution is 20ml, 20% of it needs to be sodium chloride, so 4ml is sodium cholride and then there's 16ml water, to make it up to 20ml.