Making 10% Hydrochloric acid

Discussion in 'B&W: Film, Paper, Chemistry' started by Marco Buonocore, Dec 14, 2012.

  1. Marco Buonocore

    Marco Buonocore Member

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    How would I go about making 10% hydrochloric acid? I have sodium bisulfate, sodium chloride and I can also get muriatic acid from the hardware store.

    I am interested in making a chromatic bleach that Tim Rudman suggests in pg. 121 of his book The Photographer's Master Printing Course. He suggests a bleach of 5% potassium dichromate and 10% hydrochloric acid diluted 1:1:6 with water. The formula looks similar to one in the Darkroom Cookbook (Formula #181 in the 3rd Edition).

    Thank you.
     
  2. Marco B

    Marco B Member

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    You can buy 10% hydrochloric acid as a very strong de-calcifier at some of the big chain DIY shops, so you don't have to "make it". I doubt Tim Rudman suggested making it yourself. Be careful, it bites, rinse it of with water if you get on your hands, and wear safety goggles to prevent splashes in your eyes.
     
  3. michal@hanu.la

    michal@hanu.la Member

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    Muriatic acid _is_ hydrochloric acid, just dilute it as needed.
     
  4. Gerald C Koch

    Gerald C Koch Member

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    Commerrcial grade hydrochloric acid (muriatic acid) 20 Baume is 31% hydrogen chloride. Just dilute it 1 part acid to 2 parts water.
     
    Last edited by a moderator: Dec 14, 2012
  5. pgomena

    pgomena Member

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    And add the acid to water, not water to acid!! The water can boil and splash acid around if it is added to acid.

    Peter Gomena
     
  6. paul_c5x4

    paul_c5x4 Subscriber

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    Also sold as concrete & patio cleaner in these parts - At 16%, it is still pretty nasty stuff.
     
  7. Marco Buonocore

    Marco Buonocore Member

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    Thanks all; ended up diluting muriatic acid down to the required 10%

    Going to try the bleach out later today.
     
  8. NDP_2010

    NDP_2010 Member

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    Be careful what you mix with Hydrochloric acid, some reactions can produce chlorine gas (toxic :D )