Summary questions 1. Copy and complete the sentences.
In the periodic table, all the elements in the same group have similar ____________. There are ____________ groups in the periodic table. Group ____________ is the halogens. Group 8 is the ____________ gases.
Elements in periods of the periodic table are arranged in order of increasing ____________ ____________. The period number also tells us the number of ____________ in an atom.
2. What information does the periodic table tell us about three different elements of your choice?
3. The table below shows the data for six elements: a. Locate these elements on the periodic table and identify the groups to which they belong. Element (symbol) Lithium (Li) Sodium (Na) Potassium (K) Neon (Ne) Argon (Ar) Krypton (Kr)
Melting point (°C) 180 98 64
–249 –189 –157
b. Compare the melting point patterns for group 1 and group 8. What happens to the melting point as you go down group 1 and group 8?
4. Copy the table below and use the period and group details to complete it: Period number
3
Group number 1
43 24 47 18 33
5. Research the contribution of Johann Wolfgang Döbereiner (1780–1849) and John Newlands (1837–1898) to the development of the periodic table and place them in a timeline with Mendeleev.
6. Explain why carbon dioxide does not appear in the periodic table. 7. Table salt (NaCl) and water (H2
8. Explain how: a. a positive ion forms b. a negative ion forms
Elements of Science 189 O) are both compounds. Table salt is a compound with ionic bonds
and water is a compound with covalent bonds. Explain the difference between ionic and covalent bonds.