Nuclear Atom Quiz

The Nuclear Atom

1. The diagram represents an atom.

            a. What name is given to the central part of the atom?

            b. What particles make up this central part?

            c. What particles orbit around the central part?

            d. Which part of the atom has most of its mass?

            e. Atoms are small. Roughly how many, placed in a line, would occupy one millimetre – a

                thousand, a million, a billion or a trillion?

        2. The nucleus of an atom of nitrogen is represented by the symbol:

            a. How many nucleons are there in this nucleus?

            b. What is the proton number of this nucleus and what is its neutron number?

            c. How many electrons are there in a neutral atom of this second isotope?

        3. The diagram shows what happens when alpha particles pass close to the nucleus of a gold atom.

            a. Explain why the path of an alpha particle may bend as it passes close to a gold nucleus.

            b. Explain why one of the alpha particles is undeflected.

            c. One alpha particle has been ‘back-scattered’. Explain why this has happened.