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Topic: NaOH and water  (Read 4252 times)

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Offline buck_i_h8tr

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NaOH and water
« on: March 03, 2007, 03:07:17 PM »
This seems like it would be simple but I am having trouble calculating how much sodium hydroxide (50%) I need to add to 500L of water to bring the pH to 10.

Can anyone help me with the calculation and how to do it?

thanks.

Offline Mitch

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Re: NaOH and water
« Reply #1 on: March 03, 2007, 03:13:59 PM »
Start by writing a balanced chemical equation
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Offline enahs

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Re: NaOH and water
« Reply #2 on: March 03, 2007, 03:55:54 PM »
Start by writing a balanced chemical equation

You where supposed to say "see #1". :)

Offline buck_i_h8tr

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Re: NaOH and water
« Reply #3 on: March 04, 2007, 12:14:58 PM »
OK,

1 mol of sodium hydroxide reacts with one mol of water

still doesn't help

Offline Borek

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Re: NaOH and water
« Reply #4 on: March 04, 2007, 01:30:44 PM »
1 mol of sodium hydroxide reacts with one mol of water

Huh?

Do you know what dissociation is? Do you know what water ion product is?
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Offline english

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Re: NaOH and water
« Reply #5 on: March 04, 2007, 03:46:37 PM »
First of all we need to know what that percentage means, i.e. w/v or v/v % ?

You know the pH, so you know that the pOH is pKw - pH .

Your pOH function is directly calculated from the NaOH concentration.


You also know that pOH = -log([NaOH]) .
« Last Edit: March 04, 2007, 06:50:54 PM by g english »

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