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INPUT   DATA

♥ EXAMPLE Of Input/Output

Title

Concentration of Sulfuric acid solution		% by weight of H2SO4
Desired concentration of Hydrochloric acid		% by weight of HCl

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OUTPUT   VARIABLES   &   GRAPHS

Variables	Values	Units
♦  Weight of pure H2SO4 required		per unit weight of pure HCl
♦  Weight of pure H2SO4 required		per unit weight of Hydrochloric acid solution
♦  Required weight of Sulfuric acid solution		per unit weight of Hydrochloric acid solution

Preparation Of Hydrogen Chloride

Hydrogen Chloride (HCl) gas is very soluble in water, and a solution of the gas forms Hydrochloric Acid. When 1 kg of water is saturated with the gas at 15 °C, it increases in weight to 1.75 kgm., i.e. 43% by weight of HCl in the hydrochloric acid solution.
Many Metallic Chlorides liberate Hydrogen Chloride gas, when warmed with concentrated Sulphuric Acid (H₂SO₄). Hydrogen Chloride may be prepared in the laboratory by heating concentrated Sulphuric Acid solution with Sodium Chloride, according to the following equation:

     2NaCl + H₂SO₄ => Na₂SO₄ + 2HCl ,     i.e. 1 mol of H₂SO₄ [=98.1 gm] reacts with 2 mols of HCl [=72.92 gm].

If a particular concentration by weight of hydrochloric acid [h] is desired, and sulfuric acid of known concentration [s] and sodium chloride is available. Then it is possible to estimate the amount of sulphuric acid [w] required according to the equation:

    w = [98.1/72.92]*[h/s]

Tips

    ◊ Use link EXAMPLE Of Input/Output  to demo data entry expectations and results; you may edit & use it as starting point

BIBLIOGRAPHY

• Rosenberg JL & Epstein LM; College Chemistry, Schaum's Outlines Series; McGraw Hill, New York, 1997.
• O'Leary D; University College Cork, Ireland, 2000, http://www.ucc.ie/ucc/depts/chem/dolchem/html/comp/hcl.html