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2.7: Common qualitative analysis reagents, their effects, and hazards

  • Page ID
    369426
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    Common qualitative analysis reagents, their effects, and hazards

    Reagent

    Effects

    Hazards

    6M Ammonia (\(\ce{NH4OH}\) or \(\ce{NH3}\))

    increases [\(\ce{NH3}\)], increases [\(\ce{OH^-}\)], decrease [\(\ce{H3O^+}\)], precipitates insoluble hydroxides, forms \(\ce{NH3}\) complexes

    Toxic, corrosive, and irritant

    6M Hydrochloric acid (\(\ce{HCl}\))

    increases [\(\ce{H3O^+}\)], increases [\(\ce{Cl^-}\)], decreases [\(\ce{OH^-}\)], dissolves insoluble carbonates, chromates, hydroxides, some sulfates, destroys hydroxo and \(\ce{NH3}\) complexes, and precipitates insoluble chlorides

    Toxic and corrosive

    3% Hydrogen peroxide (\(\ce{H2O2}\))

    Oxidizing agent in acidic medium, reducing agent in basic medium

    corrosive

    6M Nitric acid (\(\ce{HNO3}\))

    Increases [\(\ce{H3O^+}\)], decreases [\(\ce{OH^-}\)], dissolves insoluble carbonates, chromates, and hydroxides, dissolves insoluble sulfides by oxidizing sulfide ion, destroys hydroxo and ammonia complexes, good oxidizing agent when hot

    Toxic, corrosive, and strong oxidant

    3M Potassium hydroxide (\(\ce{KOH}\))

    Increases [\(\ce{OH^-}\)], decreases [\(\ce{H3O^+}\)], forms hydroxo complexes, precipitates insoluble hydroxides

    Toxic and corrosive

    1M Thioacetamide (\(\ce{CH3C(S)NH2}\))

    Produces \(\ce{H2S}\), i.e., a source of sulfide ion (\(\ce{S^{2-}}\)), precipitates insoluble sulfides

    Toxic and carcinogen


    This page titled 2.7: Common qualitative analysis reagents, their effects, and hazards is shared under a Public Domain license and was authored, remixed, and/or curated by Muhammad Arif Malik.

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