- Apr 20, 2016
is it 0.85 times pbno3 molecular weight which gives the moles?
That's finding the number of moles of Al2(SO4)3 and you cannot use this to find the moles of PbSO4 because it's the excess. You must use the limiting reagent to find the moles of PbSO4because we have the c=n/v we have c and v where c is 0.5 and v is 0.065 and if you times them together you get 0.0325
Sorry, I misunderstood what you were saying.We use the pbno3 moles because pbno3 and pbso4 has same mole ratio right? Or what you said just then, you always use the limiting reagent?
Sorry, I don't know this one. I forgot nearly all of this but try going through each step of the experiment and see if you can spot any inconsistencies that ariseCalcium bromide and sodium sulfate react in solution and a precipitate of calcium sulfate forms. In a certain experiment the mass of calcium sulfate formed in this reaction was calculated to be 0.80g
a) Write a balanced equation for this reaction:
CaBr2 + Na2SO4 ---> CaSO4 + 2NaBr (correct me if im wrong)
b) When the precipitate was collected, dried and weighed, its mass was only 0.55g. The experiment was repeated several times with similar results. Account for the difference between the calculated mass and the mass of the dried calcium sulfate.
What even is the aim of experiment is this? Is it to conduct gravimetric analysis of the mixture once it has been separated? Is it to simply determine which separation technique is best for each situation? Or is it simply to separate the mixture successfully?If someone could respond to my following question ASAP, that would be appreciated
Can I please have some help in regards to setting up the following practicals:
a). Separate CuSO4 (copper sulfate) from water
b). Electrolysis of Cu (copper) from Copper sulfate
Also can I please have some help in suggestions for writing up the scientific method on one of these. For the separation in a) I guess evaporation will be the technique used.
Thank you all.
The aim for practical a) would be gravimetric analysis with additional equipment (weight scale, calculator etc.) as you mentioned above.What even is the aim of experiment is this? Is it to conduct gravimetric analysis of the mixture once it has been separated? Is it to simply determine which separation technique is best for each situation? Or is it simply to separate the mixture successfully?
This will shape how you will set up the practical. If its for gravimetric analysis, you would need additional equipment (ie. weight scale, calculator etc.), than if its simply for separation.
For a) you could use evaporation, but you would lose the water and thus won't retrieve all your substances back. Using simply distillation would be more suitable, but is less practical at school.