Chapter Twelve: Atoms
A worksheet covering the structure of atoms, key atomic models (Thomson, Rutherford, Bohr), and the principles of atomic spectra. Total: 40 marks.
Section A: Fill in the Blanks [20 Marks]
Complete the following statements with the correct word or phrase.
In 1897, experiments by J. J. Thomson revealed that atoms of different elements contain negatively charged constituents called ________.
The first model of the atom, proposed by J. J. Thomson, was picturesquely called the ________ of the atom.
Rutherford's planetary model of the atom, where electrons orbit a central small volume, is also called the ________ of the atom.
In the Geiger-Marsden experiment, scattered alpha-particles produced brief light flashes, or ________, on a zinc sulphide screen.
The fact that only about 1 in ________ alpha-particles were deflected by more than 90° led Rutherford to propose the nuclear model.
Section B: Multiple Choice Questions [20 Marks]
Choose the single correct answer for each question.