Chapter Twelve: Atoms
This worksheet covers the fundamental models of the atom, from Thomson to Bohr, including atomic spectra and the quantum nature of electrons. Total: 60 marks.
Section A — One Word Answers [20 Marks]
Answer the following questions in one word or a short phrase.
Who proposed the "plum pudding" model of the atom in 1898?
What is the picturesque name for the atomic model where electrons are embedded in a uniformly distributed positive charge, like seeds in a watermelon?
What negatively charged constituents of atoms were found to be identical for all elements?
What type of particles were directed at a thin gold foil in the Geiger-Marsden scattering experiment?
According to Rutherford's model, what is the small, dense, positively charged center of an atom called?
Section B — True or False [40 Marks]
State whether the following statements are True or False, and provide a brief explanation for your answer.