Chapter Name: Structure Of Atom
Activity Name: Color with cupric chloride reaction in Structure Of Atom
This experiment involves observing the colors produced when cupric chloride and strontium chloride are introduced into a non-luminous flame. Required Items: Cupric chloride, concentrated hydrochloric acid, watch glass, platinum loop, strontium chloride.
Cupric chloride, concentrated hydrochloric acid, watch glass, platinum loop, strontium chloride.
Step by Step Procedure:
- Take a pinch of cupric chloride in a watch glass.
- Add concentrated hydrochloric acid to the cupric chloride to make a paste.
- Take a small amount of the cupric chloride paste on a platinum loop.
- Introduce the platinum loop with cupric chloride paste into a non-luminous flame (e.g., from a Bunsen burner or a gas stove).
- Observe the color of the flame.
- Clean the platinum loop thoroughly before proceeding to the next part of the experiment.
- Repeat the above steps with strontium chloride, using a fresh platinum loop.
- When cupric chloride is introduced into the flame, it produces a distinct color.
- When strontium chloride is introduced into the flame, it produces a different color.
- Handle cupric chloride and strontium chloride with care and avoid direct contact with skin or eyes.
- Perform the experiment in a well-ventilated area to prevent the build-up of toxic gases.
- Use a non-luminous flame to ensure accurate observation of the colors produced.
- Thoroughly clean the platinum loop between each test to avoid contamination and false color observations.
Lesson Learnt from Experiment:
This experiment demonstrates the concept of atomic emission spectra. The colors observed in the flame are due to the excitation of electrons in the metal ions present in the cupric chloride and strontium chloride.
Each element has a unique set of energy levels, and when electrons move from higher to lower energy levels, they emit light of specific wavelengths, resulting in the characteristic colors. By analyzing these emission spectra, scientists can identify the presence of specific elements in various substances.