10% HCl
10% HCl
Hi all,
When I'm making a 10% soln of HCl, do I start from CONC?
Seemed simple til I started to think about it (ah, but maybe I think too much!)
Hope you're having a great Friday,
When I'm making a 10% soln of HCl, do I start from CONC?
Seemed simple til I started to think about it (ah, but maybe I think too much!)
Hope you're having a great Friday,
Liz
Life keeps getting better every day!
Life keeps getting better every day!
Re: 10% HCl
Hi Liz
The conc. HCl we buy is 35%. I'm struggling a little trying to explain the maths, but I think that 28.6ml of this solution to 71.4ml of distilled water will make a 10% solution.
Someone please correct me if I'm wrong, and explain the maths.
Julie
The conc. HCl we buy is 35%. I'm struggling a little trying to explain the maths, but I think that 28.6ml of this solution to 71.4ml of distilled water will make a 10% solution.
Someone please correct me if I'm wrong, and explain the maths.
Julie
Re: 10% HCl
hi,
you do start from conc if you want to make 10%. depends what is molarity you have (con usualy is 12M or 42%)
I cheat all the time by using concentration calculator. just make sure that you chose your chemical first
http://www.trimen.pl/witek/calculators/stezenia.html
you do start from conc if you want to make 10%. depends what is molarity you have (con usualy is 12M or 42%)
I cheat all the time by using concentration calculator. just make sure that you chose your chemical first
http://www.trimen.pl/witek/calculators/stezenia.html
Cheers Jazz
- Ocean Breeze
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- Joined: 01 Jun 2006, 10:00
- Job Title: Lab Manager
- State/Location: NSW
Re: 10% HCl
Firstly, check on your conc bottle to determine what is the current strength of your conc acid.
With H Cl, it could be 10 Molar or maybe 12 Molar
We have both.
10 Molar H Cl = 32 %
12 Molar H Cl = 36%
You can then do your dilution from the starting point of stated %age.
Then do your M1 x V1 = M2 x V2 equation, just substitute % for M
eg If you want 500 ml total of the 10% H Cl. Assume that we are using the 32 % conc stock acid.
M1 V1= M2 V2
32 % x V1 = 10% x 500 ml
V1 = (10 x 500) / 32
V1 = 5000/32
V1 = 156
Therefore, you need 156 ml of your 32% stock acid, MADE UP TO 500 Mls. This will give you your 10% H Cl
sorry shockong spelling
With H Cl, it could be 10 Molar or maybe 12 Molar
We have both.
10 Molar H Cl = 32 %
12 Molar H Cl = 36%
You can then do your dilution from the starting point of stated %age.
Then do your M1 x V1 = M2 x V2 equation, just substitute % for M
eg If you want 500 ml total of the 10% H Cl. Assume that we are using the 32 % conc stock acid.
M1 V1= M2 V2
32 % x V1 = 10% x 500 ml
V1 = (10 x 500) / 32
V1 = 5000/32
V1 = 156
Therefore, you need 156 ml of your 32% stock acid, MADE UP TO 500 Mls. This will give you your 10% H Cl
sorry shockong spelling
Re: 10% HCl
Would have done the same as you Barbara - a very handy little formular that one. Can I just suggest Liz that you go back to who ever asked you for this and check that they don't just want a straight 10% solution ie the old 10mls in 100mls etc. only because it makes quite a difference to the conc. the students will use.
Cheers Trudy
Cheers Trudy
Re: 10% HCl
Many thanks to you all!
Love that calculator, Jazz - put it straight onto favourites!
Love that calculator, Jazz - put it straight onto favourites!
Liz
Life keeps getting better every day!
Life keeps getting better every day!
Re: 10% HCl
Me too!!
Who needs maths??
Julie
Who needs maths??
Julie
Re: 10% HCl
He's away, Trudy, or I would!
That's what brought me to ask all of you - 10mls of what molar HCl to start with?
Think I'll go with 10% of our CONC, currently 32%, as I'm confident it's doesn't have to be too precise - soaking pieces of string!!!!!
It's just that it brought up the question in my mind, and know I'd get an answer quickly on this wonderful site.
It's hte best resource I have!
Thanks to all,
That's what brought me to ask all of you - 10mls of what molar HCl to start with?
Think I'll go with 10% of our CONC, currently 32%, as I'm confident it's doesn't have to be too precise - soaking pieces of string!!!!!
It's just that it brought up the question in my mind, and know I'd get an answer quickly on this wonderful site.
It's hte best resource I have!
Thanks to all,
Liz
Life keeps getting better every day!
Life keeps getting better every day!
Re: 10% HCl
Sorry Liz, I think by your reply you took me the wrong way. If hes away its a bit hard, teachers are not always clear with their requests are they. It wastes alot of our precious time trying to track them down and we're not mind readers.
Good luck
Trudy
Good luck
Trudy
- Ocean Breeze
- Posts: 798
- Joined: 01 Jun 2006, 10:00
- Job Title: Lab Manager
- State/Location: NSW
Re: 10% HCl
You guys that use dilution calculators must have a lot more brain cells that I have! I dont ever use the tables or calculators, I have to do the maths. For the very reason, that if I dont use the maths, I will too soon forget the process of doing it manually. Then I am really stuck when I need to perform on the spot. Anyone else have that trouble?
Re: 10% HCl
lol , know what you mean. I do it manually as well, I'm sure you can hear the cogs ginding as I try to figure out the answer some times. The calculator site does look good though
Re: 10% HCl
No offence taken, Trudy - I knew what you meant.
I can spend more time trying to get an answer here than it takes to get a reply from someone hundreds or thousands of kilometres away. Much more time effective to keep working and check here for replies regularly than to find someone to ask, who won't debate the answer!
I'm sure you know what I mean.
Enjoy the weekend, counting down now.....
I can spend more time trying to get an answer here than it takes to get a reply from someone hundreds or thousands of kilometres away. Much more time effective to keep working and check here for replies regularly than to find someone to ask, who won't debate the answer!
I'm sure you know what I mean.
Enjoy the weekend, counting down now.....
Liz
Life keeps getting better every day!
Life keeps getting better every day!