Discovery of Electrons

Question 1

Describe Thomson’s cathode experiment

Answer 1

Thomson used a cathode (stream of electrons travelling between two charged areas) to demonstrate that there are particles (electrons) that travel towards a positive charge, suggesting a negative charge

Question 2

What is the SI unit for charge?

Answer 2

Coulomb (C)

Question 3

Describe Millikan’s oil drop experiment

Answer 3

Small oil droplets were passed through an atomizer, ionized, and the electrons were held between a positive and negative magnetic field, the charge of the ionized particles were then calculated an always found to be a whole number multiple of the charge of a single electron

Question 4

What is the charge of one electron?

Answer 4

-1.6 x 10^-19

Question 5

What is the mass to charge ratio?

Answer 5

1 g / -1.76 x 10^8 C