1. What is
meant by the periodic repetition of properties of elements?
table of elements built upon the work of previous scientists.
a) What information was available to Mendeleev when he constructed
a periodic table?
b) Mendeleev used the formulae of chlorides and hydrides
to help him group the elements. What pattern did he observe in the formulae of
chlorides and hydrides of group 1 metals?
c) How did you use similar patterns to place elements in different
groups? Give two examples.
d) What other information might have been useful to you
to help sort the element cards?
3. Look at the
group I elements in your Periodic Table. Does each group of three follow the
law of triads observed by Johann Dobereiner? Explain why or why not.
4. How has
atomic weight helped to organise the elements in your Periodic Table? Give some
5. How does
atomic number differ from atomic weight?
Mendeleev had known atomic number would it have been easier to organise the
elements? Explain why or why not.
7. Why is the
arrangement of elements into the modern Periodic Table in order of atomic
number rather than atomic weight?