100 mL of a solution contained 3.2 g of potassium nitrate.
25 mL of this solution was added to an empty 250 mL volumetric flask. Distilled water was added up
to the 250 mL mark and the flask was shaken to ensure that mixing was complete.
A pipette was used to transfer 25 mL of the resulting solution from the volumetric flask to an empty
conical flask.
What is the concentration of the potassium nitrate solution, in g L-1, in the conical flask?
A) 0.80g L-1
B) 3.20g L-1
C) 0.32g L-1
D) 8.00g L-1
E) 0.08g L-1
Chemistry is not my thing, so no guarantees down this road.
C= m/V
concentration = mass (g)/ volume(L)
concentration of potassium nitrate in the first solution = 3.2/ 100 * 10^-3
= 32 g/L
concentration of potassium nitrate in the 250 ml flask:
CāVā = CāVā
32 * 0.025 = Cā * 0.25
Cā = 0.8 g/L
I think the answer is A
https://i.imgur.com/FTikF4S.jpg
Hey, I first found the mass of KNO3 of 25ml in the first solution, and then added that to the volumetric flask, which has 250 mL but the question says that only 25 mL of the resulting solution was transferred to an empty conical flask so I found the mass for 25 mL and then divided it by 25ml to find the grams per liter and (make sure everything is converted to liter at the end!).
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@Sarasalih thx for the heads up! turns out that I miscalculated the above equation because I did it quickly in my head. It will actually give 3.2 for C2 , so it matches your answer!