Physics Demo Number: 031

Approximate Run Time: 10 min

Direct Evidence of the Atomic Nature of Matter by Electrolysis

Demo Description

Run a current from a battery through water (with 10% sulphuric acid) to separate the hydrogen and oxygen in the water. Bubbles of the two gases can be separated into the two tubes and measured.

 

Scientific Principles

  • Electrolysis -( Decompose water into hydrogen and oxygen by passing an electrical current through the water.)

  • Evidence for Atomic Nature of Matter

 

Equipment

  • Electrolysis apparatus

  • Hardware stand

  • Black light

 

Equipment Location

  • Pictured Apparatus now living in [A-2-2].

  • Black Light [C-2-5]

  • 6 volt dry cell battery [A-2-2]

 

Instructions

The photo shows the electrolysis apparatus on its dedicated hardware stand, used to decompose water into hydrogen and oxygen.

The solution in it is 10% Sulphuric Acid  (to make it conducting) with some Fluorescein added to allow easy viewing of the fluid under the black light. The battery is a 6V dry cell.

One can comment on the water disassociating into two gaseous components as direct evidence of the atomic nature of matter.
  
Writeup created by David A. Burba
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