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Nitric Acid

Concentrate Nitric Acid

H2SO4 + 2 NaNO3 --> Na2SO4 + 2HNO3

The big difference in my recipie is the solubility of the sodium sulfate salt (as opposed to sodium hydrogen sulfate you produce) and the fact that my equation yields twice the nitric acid at a higher temperature ( no dry ice, just salted ice ).

I've run the numbers like you did and ended up with about 160 mL of 50% nitric (give or take a few percent) for a single mole of 96% sulfuric and using 100mL H2O to dissolve the nitre.

I won't bore everyone with the math, but here's my summary.

Reaction:

• Bring 100 mL of Distilled Water in a 500 mL pyrex beaker to 100 C
• Add the Nitre of your choice (202 gm K / 170 gm Na)
• Stir until Nitre is completely dissolved, let cool below boiling
• SLOWLY add 56 mL conc (96%+) Sulfuric Acid to Hot Nitre solution while stirring, DON'T allow the solution to boil!
• Allow solution to cool to room temp (DO NOT SKIP - VESSEL WILL SHATTER IF PUT ON ICE WHILE HOT!!!)
• When vessel reaches room temp (25 °C) put the vessel in the freezer or on a salt water ice bath
• Let stand until temperature of mixture reaches -5 °C
• Let stand at -5 °C until all percipitate settles
• Pour the COLD solution off into glass container with tightly sealed lid DO NOT POUR OFF ANY OF THE SALT IN THE BOTTOM!!!
• Makes ~160 mL ~50% HNO3
K= Potassium NA= Sodium

This acid in turn can be used to make true AR with the standard 4:1 recipie (HCl:HNO3).