This is the only problem I missed on my chemsitry exam and I have no idea how to work it, can anyone explain it to me simply?
Calculate the concentration of the solution formed when 102 ml of 9.9 M HCl is diluted with 525 ml of water.
The correct answer to this problem is 1.61. I have asked this before, but all of the answers given so far have been wrong. I know the answer, however, I need to know how to do this problem step by step so I can do these for future exams. Thank you!
2006-06-27 05:07:15 · 7 answers · asked by trinitarianwiccan 2 in Science & Mathematics ➔ Chemistry
Use the equation M1V1 = M2V2
M1 is the molarity of the HCL or 9.9 M
V1 is the first volume of 102 ml but it needs to be changed to Liters. So it is 0.102L
V2 is the total volume of the final solution so 525 ml (0.525 L) + V1 or 0.102L = 0.627
M2 is what you are looking for - the final concentration or molarity.
Rearrange the equation to ((M1)(V1)) / (V2) = M2
(0.102L)(9.9M) / (0.627) = 1.61 M
Hope this helped!
2006-06-27 05:17:01 · answer #1 · answered by BeC 4 · 0⤊ 0⤋
Calculate the number of moles of HCL you have in the original solution. Then divide the number of moles by the total volume you have at the end (525 + 102). Remember to convert to liters, not milliliters.
2006-06-27 12:14:26 · answer #2 · answered by Risa M 1 · 0⤊ 0⤋
V1C1=V2C2
Volume 1 (in Liters) = .102 L
Concentration (in moles) 1 = 9.9 M
Volume 2 (in Liters) = .627 L (.102 + .525)
Concentration 2 (in moles) = ?
Rearrange to (V1C1)/V2 = C2
This gives you (.102 x 9.9) / (.627) = 1.61 M
2006-06-27 12:10:32 · answer #3 · answered by Greg M 2 · 0⤊ 0⤋
9.9x102/627
627 = 525+102
2006-06-27 13:07:00 · answer #4 · answered by ag_iitkgp 7 · 0⤊ 0⤋
9.9 M = 9.9 mol HCl/L
9.9 mol HCl/L x 0.102 L HCl solution = 1.0098 mol HCl in solution
0.102 L + 0.525 L = 0.627 L total solution after dilution
1.0098 mol HCl / 0.627 = 1.61 mol HCl/L after dilution
2006-06-27 13:03:52 · answer #5 · answered by scott_d_webb 3 · 0⤊ 0⤋
i hate to break it to you but they weren't all wrong. they just weren't all complete. it's all based on the same formula
M1V1=M2V2 you just have to remember to use the total volume of solution not just the parts.
2006-06-27 12:40:35 · answer #6 · answered by shiara_blade 6 · 0⤊ 0⤋
definition of Molarity = moles/liter,
9.9 moles/1L x 1L/1000mL x 102mL = 1.0098 moles of HCL
1.0098 moles HCL/(102mL+525mL) x1000mL/1L = 1.613M
2006-06-27 16:27:13 · answer #7 · answered by John P 1 · 0⤊ 0⤋