焰色反应对比实验

测试多种金属以建立焰色参考表

Flame Tests Intermediate (High School) 45 分钟 ~$25.00

目标

对六种不同金属盐进行焰色反应，创建用于定性分析的特征焰色参考表。

背景

This comprehensive flame test lab tests multiple metal salts side by side, building a reference chart that students can use for unknown identification. By comparing the flame colors of lithium, sodium, potassium, calcium, strontium, and copper directly, students develop the observational skills needed for qualitative chemical analysis.

安全警告

  • Wear safety goggles at all times
  • Wear gloves when handling copper chloride
  • Handle HCl with care — avoid contact with skin
  • Keep hair tied back near open flames
  • Clean wire between each test to prevent cross-contamination

所需PPE

goggles gloves lab_coat

材料

  • Lithium chloride (LiCl) (0.5 g)
  • Sodium chloride (NaCl) (0.5 g)
  • Potassium chloride (KCl) (0.5 g)
  • Calcium chloride (CaCl₂) (0.5 g)
  • Strontium chloride (SrCl₂) (0.5 g)
  • Copper(II) chloride (CuCl₂) (0.5 g)
    Toxic
  • Hydrochloric acid (HCl) (50 mL)
    1M concentration
  • Cobalt blue glass (1 piece)
    For potassium identification

设备

Bunsen burner Nichrome wire loop 6 labeled watch glasses Forceps Lab notebook

步骤

1

Prepare six labeled watch glasses, each containing a small amount of one metal salt.

3 分钟 Wear gloves for copper chloride
2

Clean the nichrome wire thoroughly by repeatedly dipping in HCl and heating until the flame shows no color.

3 分钟
3

Test lithium chloride first. Dip wire in HCl, then into the salt, and hold in the flame. Record the crimson-red color.

3 分钟
4

Clean the wire thoroughly. Test sodium chloride and record the bright yellow flame.

3 分钟
5

Clean the wire. Test potassium chloride. Observe with naked eye, then through cobalt blue glass. Record the lilac/violet color.

4 分钟
6

Clean the wire. Test calcium chloride and record the orange-red flame.

3 分钟
7

Clean the wire. Test strontium chloride and record the scarlet-red flame.

3 分钟
8

Clean the wire. Test copper(II) chloride and record the blue-green flame.

3 分钟
9

Create a complete reference chart organizing the metals by flame color from red through yellow to green and violet.

5 分钟

预期结果

A complete flame color reference chart: Li (crimson-red), Sr (scarlet-red), Ca (orange-red), Na (yellow), Ba (yellow-green if tested), Cu (blue-green), K (lilac/violet through cobalt glass). Each color should be distinguishable from the others.

清理

Clean the wire with HCl. Dispose of copper waste in the heavy metal waste container. Dispose of remaining salts per lab protocol. Clean and dry all watch glasses.

详情

类别
Flame Tests
难度
Intermediate (High School)
时长
45 分钟
预估费用
$25.00
步骤数
9
材料
8

更多实验

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Frequently Asked Questions

What is the objective of 焰色反应对比实验?
对六种不同金属盐进行焰色反应，创建用于定性分析的特征焰色参考表。
How difficult is 焰色反应对比实验?
This experiment is rated as Intermediate (High School). It takes approximately 45 minutes to complete.
What safety precautions are needed for 焰色反应对比实验?
Key safety precautions include: Wear safety goggles at all times; Wear gloves when handling copper chloride; Handle HCl with care — avoid contact with skin.
What materials are needed for 焰色反应对比实验?
The main materials required are: Lithium chloride (LiCl), Sodium chloride (NaCl), Potassium chloride (KCl), Calcium chloride (CaCl₂), Strontium chloride (SrCl₂).
What results should I expect from 焰色反应对比实验?
A complete flame color reference chart: Li (crimson-red), Sr (scarlet-red), Ca (orange-red), Na (yellow), Ba (yellow-green if tested), Cu (blue-green), K (lilac/violet through cobalt glass). Each color should be distinguishable from the others.