Uji Beilstein untuk Halogen

Mendeteksi atom halogen dalam senyawa organik menggunakan uji nyala kawat tembaga

Qualitative Analysis Beginner (Middle School) 25 menit ~$5,00

Tujuan

Tentukan apakah senyawa organik mengandung atom halogen (Cl, Br, I) menggunakan uji kawat tembaga Beilstein.

Latar Belakang

The Beilstein test is a simple qualitative test for halogens in organic compounds. A copper wire is heated in a flame to form copper(II) oxide, then dipped in the test substance and returned to the flame. If a halogen is present, volatile copper halide forms and imparts a green or blue-green color to the flame. The test is sensitive but not specific (it does not distinguish between Cl, Br, and I, and can give false positives with some nitrogen compounds).

Peringatan Keselamatan

  • Chloroform is toxic — avoid inhalation and skin contact
  • Work in a fume hood when testing volatile organics
  • Hot copper wire can cause burns
  • Keep flammable solvents away from the flame

APD yang Diperlukan

goggles gloves lab_coat

Bahan

  • Copper wire (20 gauge) (15 cm)
    Make a small loop at one end
  • Chloroform (CHCl₃) (2 mL)
    Positive control
  • Ethanol (C₂H₅OH) (2 mL)
    Negative control
  • Unknown organic samples (2 mL each)
    3–4 samples
  • Cork or holder for copper wire (1)

Peralatan

Bunsen burner Watch glasses (6) Forceps

Prosedur

1

Heat the copper wire loop in the oxidizing zone of the Bunsen burner until it glows red and no green color is visible (this burns off contaminants and forms CuO).

3 menit Wire is extremely hot
2

Allow the wire to cool slightly, then dip it into the chloroform (positive control). Return the wire to the flame.

3 menit Chloroform is volatile — use fume hood
3

Observe the bright green flame (positive result for halogen). Record the color and intensity.

2 menit
4

Clean the wire by heating until green color disappears. Repeat the test with ethanol (negative control). No green color should appear.

3 menit
5

Test each unknown sample using the same procedure. Record whether each gives a positive (green) or negative result.

10 menit Clean wire between samples
6

Record all results and identify which unknowns likely contain halogen atoms.

4 menit

Hasil yang Diharapkan

Chloroform produces a vivid green flame (positive). Ethanol produces no green color (negative). Halogen-containing unknowns show green coloration of varying intensity.

Pembersihan

Allow copper wire to cool. Store organic waste in halogenated or non-halogenated solvent waste containers as appropriate. Wipe down surfaces.

Detail

Kategori
Qualitative Analysis
Tingkat Kesulitan
Beginner (Middle School)
Durasi
25 menit
Perkiraan Biaya
$5,00
Langkah
6
Bahan
5

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Frequently Asked Questions

What is the objective of Uji Beilstein untuk Halogen?
Tentukan apakah senyawa organik mengandung atom halogen (Cl, Br, I) menggunakan uji kawat tembaga Beilstein.
How difficult is Uji Beilstein untuk Halogen?
This experiment is rated as Beginner (Middle School). It takes approximately 25 minutes to complete.
What safety precautions are needed for Uji Beilstein untuk Halogen?
Key safety precautions include: Chloroform is toxic — avoid inhalation and skin contact; Work in a fume hood when testing volatile organics; Hot copper wire can cause burns.
What materials are needed for Uji Beilstein untuk Halogen?
The main materials required are: Copper wire (20 gauge), Chloroform (CHCl₃), Ethanol (C₂H₅OH), Unknown organic samples, Cork or holder for copper wire.
What results should I expect from Uji Beilstein untuk Halogen?
Chloroform produces a vivid green flame (positive). Ethanol produces no green color (negative). Halogen-containing unknowns show green coloration of varying intensity.