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Shackleford
Jul29-08, 10:50 PM
1. The problem statement, all variables and given/known data

Find the molarity of the solution (salt and any excess reagent after reaction of 250 mL of 0.05 M Ba(OH)2 with 200 mL of 0.08 M HNO3.

2. Relevant equations



3. The attempt at a solution

I am drawing a blank. Here's the balanced equation

Ba(OH)2 + 2HNO3 ===> 2H2O + Ba(NO3)s

Ba(OH) .0125 moles

2HNO3 .016 moles

Borek
Jul30-08, 05:07 AM
Simple stoichiometry, this is a limiting reagent (http://www.chembuddy.com/?left=balancing-stoichiometry&right=limiting-reagents) question. Your reaction equation is almost OK (chack barium nitrate formula, but I suppose that's a typo) and is a correct first step to solution.

Borek
--
equation balancer and stoichiometry calculator (http://www.chembuddy.com/?left=EBAS&right=equation-balancing-stoichiometry)

Shackleford
Jul30-08, 08:43 AM
Why can I not edit my own damn post?

Borek
Jul30-08, 08:56 AM
You can for 30 minutes, or something like that.

Shackleford
Jul30-08, 09:07 AM
You can for 30 minutes, or something like that.

Ok, well, Ba(NO3)2, correct?

Borek
Jul30-08, 09:47 AM
Exactly.

Ba(OH)2 + 2HNO3 -> Ba(NO3)2 + 2H2O

Now try the limiting reagent approach.

Shackleford
Jul30-08, 11:46 AM
Exactly.

Ba(OH)2 + 2HNO3 -> Ba(NO3)2 + 2H2O

Now try the limiting reagent approach.

I used the number of moles not grams to find the limiting reagent, which is nitric acid. Only .008 moles of barium nitrate will be formed.

.008 moles/.450 L = .017 M

Borek
Jul30-08, 02:05 PM
0.008 Ba(NO3)2 is a correct intermediate result. But that's not what you were asked about.

Borek
--
equation balancer and stoichiometry calculator (http://www.chembuddy.com/?left=EBAS&right=equation-balancing-stoichiometry)

Shackleford
Jul30-08, 02:13 PM
0.008 Ba(NO3)2 is a correct intermediate result. But that's not what you were asked about.

Borek
--
equation balancer and stoichiometry calculator (http://www.chembuddy.com/?left=EBAS&right=equation-balancing-stoichiometry)

I know. Check my previous post. I put the molarity of the solution.

Borek
Jul30-08, 02:49 PM
It is not all. Excess reagent is still present in the solution in unchanged form.

Shackleford
Jul30-08, 02:53 PM
It is not all. Excess reagent is still present in the solution in unchanged form.

Ah. I forgot about that.

Borek
Jul30-08, 03:02 PM
You should list every ion and its concentration separately. EOT for me.

Borek
--
equation balancer and stoichiometry calculator (http://www.chembuddy.com/?left=EBAS&right=equation-balancing-stoichiometry)

Shackleford
Jul30-08, 03:10 PM
You should list every ion and its concentration separately. EOT for me.

Borek
--
equation balancer and stoichiometry calculator (http://www.chembuddy.com/?left=EBAS&right=equation-balancing-stoichiometry)

I haven't done a limiting reagent problem in well over two years. EOT?

chemisttree
Jul31-08, 11:35 AM
End Of Thread, I believe. Do you understand the answer?