Chemistry
Required Practicals
C12.5 - Use chemical tests to identify unknown compounds
Start with unknown
Test for Carbonate
Testing for Carbonates, and Halides, or Sulfates
Add dilute nitric acid, because adding Hydrochloric Acid would prevent you from testing for Halides.
Acid + Carbonate > Salt + Carbon Dioxide + Water
MgCo3 + HNO3 > Mg(NO3)2 + CO3 +H2O
Test for Halide
Sliver Nitrate + Sodium Halide > Sodium Nitrate + Silver Halide
\(AgNO_3\)(aq) + \(NaBr\)(aq) > \(NaNO_3\)(aq) + \(AgBr\)(s)
\(AgNO_3\)(aq) + \(NaI\)(aq) > \(NaNO_3\)(aq) + \(AgI\)(s)
\(AgNO_3\)(aq) + \(NaCl\)(aq) > \(NaNO_3\)(aq) + \(AgCl\)(s)
Test for Sulfates
\(AgCl\) will be present as a white precipitate
\(AgBr\) will be present as a cream precipitate
\(AgI\) will be present as a yellow precipitate
Potassium Sulfate + Barium Chloride > Potassium Chloride + Barium Sulfate
To prove existence of \(CO_2\), run gas through limewater, and if the limewater goes cloudy, then \(Co_2\) is present
\(K_2SO_4\)(aq) + \(BaCl_2\)(aq) > \(2KCl\)(aq) + \(BaSO_4\)(s)
Safety: Wear chemical splash-proof eye protection
\(BaSO_4\) would be present as a white precipitate
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