Metal İyonları için Boraks Boncuk Testi

Boraks eritme işleminde oluşan renkli cam boncuklarla geçiş metallerini tanımlama

Qualitative Analysis Intermediate (High School) 45 dak ~$8,00

Hedef

Geçiş metal iyonlarını, boraks (sodyum tetraborat) cam boncuğuna eritildiğinde oluşturdukları karakteristik renklerle tanımlamak.

Arka Plan

The borax bead test is an elegant method for identifying transition metal ions. When borax (Na₂B₄O₇·10H₂O) is heated, it loses water and forms a clear glassy bead of sodium metaborate. When a metal salt is dissolved into this bead, the metal ions become trapped in the glass matrix, producing characteristic colors. The color often differs between the oxidizing flame (outer cone) and reducing flame (inner cone), providing additional diagnostic information.

Güvenlik Uyarıları

  • Molten borax beads are extremely hot
  • Chromium compounds are irritants — avoid dust inhalation
  • Do not touch hot beads — let cool on a watch glass
  • Cobalt compounds are toxic if ingested

Gerekli KKD

goggles gloves lab_coat

Malzemeler

  • Borax (Na₂B₄O₇·10H₂O) (5 g)
    Powdered
  • Metal salt samples (0.5 g each)
    CuSO₄, CoCl₂, NiCl₂, FeCl₃, MnCl₂, Cr₂O₃
  • Unknown metal salt (0.5 g)

Ekipman

Platinum wire loop (or nichrome alternative) Bunsen burner Forceps Watch glasses (7)

Prosedür

1

Make a small loop at the end of the platinum wire. Heat the loop in the hottest part of the flame until red-hot.

2 dak Wire is very hot
2

Dip the hot wire into powdered borax. Return to the flame and heat until a clear, transparent glass bead forms. Repeat dipping and heating if needed to build up the bead.

5 dak
3

Touch the hot bead to a tiny amount of CuSO₄ powder. Return to the oxidizing flame (outer cone). Observe the color (should be blue-green).

5 dak
4

Now heat the same bead in the reducing flame (inner cone, blue). The color may change to red (metallic copper).

3 dak
5

Make fresh beads and repeat for each metal salt. Record colors in both oxidizing and reducing flames, both hot and cold.

20 dak
6

Test the unknown salt and match the bead colors to your reference chart.

10 dak

Beklenen Sonuçlar

Cu: blue-green (oxidizing), red (reducing). Co: deep blue (both). Ni: gray-brown (oxidizing), gray (reducing). Fe: yellow-brown (oxidizing), green (reducing). Mn: violet (oxidizing), colorless (reducing). Cr: green (both, darker in reducing).

Temizlik

Allow all beads to cool completely. Dispose of transition metal waste appropriately. Clean the platinum wire by fusing with fresh borax until clear.

Ayrıntılar

Kategori
Qualitative Analysis
Zorluk
Intermediate (High School)
Süre
45 dak
Tahmini Maliyet
$8,00
Adımlar
6
Malzemeler
3

Daha Fazla Deney

Alev Emisyon Spektroskopisi 60 min Anyon Tayin Testleri 60 min Bilinmeyen Madde Tanımlama Görevi 75 min Bitki Pigmentlerinin Kromatografisi 60 min Çökeltme ile Katyon Tayini 90 min Halojenler için Beilstein Testi 25 min Karbonhidratlar için Nişasta-İyot Testi 30 min pH İndikatörü Gökkuşağı 45 min Sabun Çözeltisiyle Su Sertliği Testi 40 min

Frequently Asked Questions

What is the objective of Metal İyonları için Boraks Boncuk Testi?
Geçiş metal iyonlarını, boraks (sodyum tetraborat) cam boncuğuna eritildiğinde oluşturdukları karakteristik renklerle tanımlamak.
How difficult is Metal İyonları için Boraks Boncuk Testi?
This experiment is rated as Intermediate (High School). It takes approximately 45 minutes to complete.
What safety precautions are needed for Metal İyonları için Boraks Boncuk Testi?
Key safety precautions include: Molten borax beads are extremely hot; Chromium compounds are irritants — avoid dust inhalation; Do not touch hot beads — let cool on a watch glass.
What materials are needed for Metal İyonları için Boraks Boncuk Testi?
The main materials required are: Borax (Na₂B₄O₇·10H₂O), Metal salt samples, Unknown metal salt.
What results should I expect from Metal İyonları için Boraks Boncuk Testi?
Cu: blue-green (oxidizing), red (reducing). Co: deep blue (both). Ni: gray-brown (oxidizing), gray (reducing). Fe: yellow-brown (oxidizing), green (reducing). Mn: violet (oxidizing), colorless (reducing). Cr: green (both, darker in reducing).