Ammonium chloride: Difference between revisions

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==Purification==
==Purification==
===Sublimation/dissociation===
===Sublimation/dissociation===
This could also replace the evaporation iterations in the synthesis. [[Ammonium chloride]] dissociates (reversibly) into [[ammonia]] and [[hydrogen chloride]] at 337.6 °C. If the gasses are cooled on a surface, they react to re-form [[ammonium chloride]], so placing a cold boiling flask over a beaker of solid ammonium chloride, then heating the beaker would transport  ''just'' the ammonium chloride to the bottom of the flask.
This could also replace the evaporation iterations in the synthesis. [[Ammonium chloride]] dissociates (reversibly) into [[ammonia]] and [[hydrogen chloride]] at 337.6 °C. If the gases are cooled on a surface, they react to re-form [[ammonium chloride]], so placing a cold boiling flask over a beaker of solid ammonium chloride, then heating the beaker would transport  ''just'' the ammonium chloride to the bottom of the flask.
==Testing==
==Testing==
==Storage==
==Storage==

Revision as of 16:10, 13 July 2020

 
Ammonium chloride
aka Sal ammoniac
Chemical formula NH4Cl
OTP appearance white/clear crystals 
Index of refraction 1.642 
Molar Mass(g/mol) 53.49 
Density(g/cc) 1.5274 
Melting Point(°C) 338(decomp) 
Boiling Point(°C) 520 
Solubility in water(g/L) 383 
Solubility in ethanol(g/L) 4.25 
Solubility in methanol(g/L) 23.7 
Solubility in ether(g/L) insoluble 
Solubility in acetone(g/L) sparingly
NFPA 704
NFPA704.png
0
2
0
 

Uses

Other

Natural occurrence

  • Does occur naturally as the mineral sal ammoniac

Hazards

Production

Extraction

Synthesis

via sodium chloride

Bubble carbon dioxide through a solution of sodium chloride, ammonia, and water, producing ammonium chloride and sodium bicarbonate[1][2][3]:

NaCl(aq) + NH3(aq) + H2O(l) + CO2(g) NaHCO3(s) + NH4Cl(aq)
  1. Prepare an ammonia solution with a density of 0.907 (25% w/w) at 20°C
  2. Heat the solution to 40°C
  3. Add an excess of Salt
  4. Decant/filter solution
  5. Discard residue (undissolved salt)
    Solution is NH4OH + NaCl + NH4Cl + NaOH
  6. Chill to -11°C
  7. Precipitate is ammonium chloride (Approximately 10% w/w of the saturated salt solution)
  8. Solution is NH4OH + NaCl + NaOH with some remaining dissolved ammonium chloride, and weighs approximately 90% of the original saturated salt solution.

via hydrochloric acid

Combine ammonia and hydrochloric acid

NH3 + HCl NH4Cl

via calcium chloride

(or magnesium chloride)

  1. Bubble carbon dioxide through a solution of ammonia and magnesium or calcium chloride, precipitating magnesium or calcium carbonate:
    2 NH3 + CaCl2 + H2O + CO2 2 NH4Cl + CaCO3
  2. Filter
  3. Discard residue
  4. Evaporate filtrate to crystallize ammonium chloride

Purification

Sublimation/dissociation

This could also replace the evaporation iterations in the synthesis. Ammonium chloride dissociates (reversibly) into ammonia and hydrogen chloride at 337.6 °C. If the gases are cooled on a surface, they react to re-form ammonium chloride, so placing a cold boiling flask over a beaker of solid ammonium chloride, then heating the beaker would transport just the ammonium chloride to the bottom of the flask.

Testing

Storage

Disposal

See Also

References