If your % Al is less than 99%, explain two possible sources of uncertainty that could account for your low value. If your % Al is greater than 100%, explain two possible sources of uncertainty that could account for your high value. 2. (4) If all the connections in your apparatus are not air-tight and some H escapes (after the initial volume has been recorded), will the reported percent Al in the sample be greater or less than the actual percent? Explain. 3. (3) Look up aluminum on-line and list 3 uses (medical or otherwise). Do not include words in your answer that you do not know, unless you include a definition