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Group IA
Note that in general, we have M(s) + H2O(l) ---> MOH(aq) + H2(g);
as mentioned, Li forms an oxide, Na forms a peroxide, and K a superoxide in their reactions with oxygen.
Be sure to comment on the rates of reaction of Li, Na, and K with oxygen and water.
Group IIA
If you observed a reaction with water, it is of the same general form as the reactions of the group 1A metals with water (but the formula of the hydroxide is different!) Also notice that Metal + acid ---> salt + H2(g).
Mg and Ca both form simple oxides when burned in air; be sure to comment on any differences in reaction rates you observed between these elements and the group 1A elements.
Group IIIA
Notice that B and Al are unreactive towards water (B dissolving in water does not constitute a reaction!) If either of these elements reacted towards acid, then a salt and hydrogen gas was produced.
Group IVA
IF a reaction was observed with acid, then the products were again a salt and hydrogen gas. On the basis of metallic character, we would expect Pb to be more reactive towards acids than Sn; was this the case? Also note that Sn and Pb both commonly form the +2 ions.
Group VA
Note that red phosphorus exists as P4, and forms P4O10 when burned. This nonmetal oxide is acidic in aqueous solution - what acid do you think will form? Bi is pretty unreactive (perhaps you observed a reaction with acid when heated.)
Group VIA
You've done these reactions before - S exists as S8, and reacts with oxygen to form sulfur dioxide and trioxide. These are acidic oxides - they produce acidic aqueous solutions.
Group VIIA
Rank the halogens in terms of their reactivities towards each other. You may write net ionic equations for these reactions.
The report should contain a brief intro, the usual methods section, and a results and discussion section. For the reactions in each group, write a brief observation and the pertinent reaction. At the end of the results for each group, comment on the reactivities of the elements (see the lab book.)
As a conclusion to your lab reoprt, write a paragraph summarizing the way in which the physical and chemical properties of the elements vary with their positions in the periodic table.