standardize NaCl solution

[snowysummer]

Can anybody tell me what primary standard is usually used to standardize NaCl?

[akcapr]

Whats a primary standard?

[snowysummer]

primary standard is a substance that has high purity. Dissolve the standard into solution, then titrate it against a sample to determine the sample's concentration.

[akcapr]

Its hard to understand your question, try explaining it better. Are titrateing an acid or something?

[woelen]

Can anybody tell me what primary standard is usually used to standardize NaCl?

This article may help you.

 

http://www.chem.uidaho.edu/faculty/ifcheng/Chem%20253/labs/Experiment%206.doc

 

Whether silver ntirate is a primary standard or not is debated somewhat. I think it can be a primary standard, provided a really high grade sample is used. In the paper, I have given here, the silver nitrate must be standardized. You could do the other way around, standardizing your NaCl.

[scientistsahai]

A primary standard

 

A substance of a known high degree of purity that undergoes one invariable reaction with the other reactant of interest.

 

A primary standard is a reagent that is extremely pure, stable, has no waters of hydration, and has a high molecular weight.

 

Some primary standards for titration of acids:

sodium carbonate: Na2CO3, mol wt. = 105.99 g/mol

tris-(hydroxymethyl)aminomethane (TRIS or THAM): (CH2OH)3CNH2, mol wt. = 121.14 g/mol

This is what you were looking for :

Some primary standards for titration of bases:

potassium hydrogen phthalate (KHP): KHC8H4O4, mol wt. = 204.23 g/mol

potassium hydrogen iodate: KH(IO3)2, mol wt. = 389.92 g/mol

 

Some primary standards for redox titrations:

potassium dichromate: K2Cr2O7, mol wt. = 294.19 g/mol

[insane_alien]

i made some primary standards on wednesday. too easy. silver nitrate is the primary standard for NaCl and NaCl is the primary standard for AgNO3.

[ecoli]

Funny, I just did that for my chem lab, about five minutes ago... accept we were using a primary standard of KHP to find the concentration of NaOH. Same concept, though.

[akcapr]

WHy cant you jsut use say KOH or NaOH as a titration base? I know you can but why isnt it "standard"?

[jdurg]

Because NaOH and KOH both absorb water from the air in their 'pure' form, and solutions of the bases absorb CO2 from the air to form the bicarbonates. Since the composition of your starting compound changes as soon as you open the bottle, it cannot be used as a standard.