カリウム炎色反応

ライラック/紫色の炎でカリウムを同定する

Flame Tests Beginner (Middle School) 20 分 ~$6.00

目的

カリウムイオンが生じるライラック/紫色の炎色を観察し、コバルトブルーガラスを使ってナトリウム汚染と区別する方法を学ぶ。

背景

Potassium produces a pale lilac or violet flame when heated. The emission occurs at 766.5 nm and 769.9 nm (near-infrared/deep red doublet). Because the flame is quite faint and easily overwhelmed by sodium's intense yellow, cobalt blue glass is used as a filter to block sodium emission and reveal potassium's true color.

安全上の警告

  • Wear safety goggles at all times
  • Keep hair tied back near open flames
  • Handle HCl with care

必要なPPE

goggles lab_coat

材料

  • Potassium chloride (KCl) (1 g)
  • Hydrochloric acid (HCl) (10 mL)
    1M concentration
  • Cobalt blue glass (1 piece)
    For filtering sodium light

器具

Bunsen burner Nichrome wire loop Watch glass Forceps

手順

1

Clean the nichrome wire thoroughly by dipping in HCl and heating.

2 分
2

Place potassium chloride on the watch glass and collect a sample on the clean wire.

1 分
3

Hold the sample in the Bunsen burner flame. Observe with the naked eye first.

2 分
4

Now observe the flame through cobalt blue glass to filter out any sodium contamination.

2 分
5

Record the difference in appearance with and without the cobalt blue glass filter.

2 分

予想される結果

Without the filter, you may see a faint lilac color possibly masked by yellow from sodium impurities. Through the cobalt blue glass, a clear violet/lilac flame should be visible as the glass absorbs the yellow sodium emission.

後片付け

Clean the wire loop with HCl. Return cobalt blue glass to storage.

詳細

カテゴリ
Flame Tests
難易度
Beginner (Middle School)
所要時間
20 分
推定費用
$6.00
ステップ数
5
材料
3

その他の実験

カルシウム炎色反応 15 min ストロンチウム炎色反応 15 min ナトリウム炎色反応 15 min バリウム炎色反応 20 min リチウム炎色反応 15 min 炎色反応比較実験 45 min 銅炎色反応 15 min

Frequently Asked Questions

What is the objective of カリウム炎色反応?
カリウムイオンが生じるライラック/紫色の炎色を観察し、コバルトブルーガラスを使ってナトリウム汚染と区別する方法を学ぶ。
How difficult is カリウム炎色反応?
This experiment is rated as Beginner (Middle School). It takes approximately 20 minutes to complete.
What safety precautions are needed for カリウム炎色反応?
Key safety precautions include: Wear safety goggles at all times; Keep hair tied back near open flames; Handle HCl with care.
What materials are needed for カリウム炎色反応?
The main materials required are: Potassium chloride (KCl), Hydrochloric acid (HCl), Cobalt blue glass.
What results should I expect from カリウム炎色反応?
Without the filter, you may see a faint lilac color possibly masked by yellow from sodium impurities. Through the cobalt blue glass, a clear violet/lilac flame should be visible as the glass absorbs the yellow sodium emission.