Re: Chemistry question :)
 

Incog gets out deckchair and drink,gets comfy and waits for Theodoric to arrive. slurp,slurp.

Re: Chemistry question :)
 

ok ppm is mg/kg

you want 100mls or 0.1kg of solution with 2.5 mg/kg concentration - i.e. 0.25mg of chloride ion.

50ppm is 50mg of chloride ion per litre so you would take 0.005 ml of the original solution? (ignoring density effects;) )

Re: Chemistry question :)
 

I'm waiting for Dr. Exacters to reply to my last post. What manners are that? Somebody gives an answer, the reply is: 'how did you arrive at that'?, and then he bloody disappears?

I want my grade. NOW!!!!! :afire: (and feedback on how to improve my answer if/when it's wrong) :)

Re: Chemistry question :)
 

It needs to be diluted by a factor of of 50/2.5 = 20. 1/20 of 100 is 5. So, take 5 ml of the 50 ppm solution and dilute to 100 ml.

Re: Chemistry question :)
 

I've just noticed this. I'm obviously getting a reputation for something or other. :)

PS It's not specifically a chemistry question, more a maths question on proportions, the sort of thing that was taught in school when I was a young lad (mutter, mumble, things were different in my young days . . .).

Re: Chemistry question :)
 

5ml is correct

Re: Chemistry question :)
 

Am I going to get a "see me" written in red :erm:

Re: Chemistry question :)
 

5ml of 50ppm solution = 5/1000 x 50 mg = 0.25mg

you are correct - my .005 was in kg/litres, not ml :dunce:

- can I have marks for my 'workings out' :D

Re: Chemistry question :)
 

Full marks to PEM then, as he got it first...

Re: Chemistry question :)
 

I'm probably getting extra homework :D

Re: Chemistry question :)
 

That'll cut down your postings.;)

Re: Chemistry question :)
 

:dunce: Ramrod :dunce: Me

sat at the back of the class :wavey:

Re: Chemistry question :)
 

tries to be good at sport, so the 'nerd' sticker, falls off - and I got it wrong:)

Re: Chemistry question :)
 

It's really annoying because I actually got A level chemistry....but when you don't use it for 16 years.... :rolleyes: :shrug:
...but thanks for the moral support :ghugs:

Re: Chemistry question :)
 

See Me later, girl.............