if Maalox is mixed with 40ml of 0.1 M HCI and isn't neutralized, how much extra help with this antacid pill need to neutralize 40ml of 0.1 M HCL by adding 0.05 M NaOH drop by drop to back-tritrate the solution until the pH is neutral?
Maalox is a trade name for a home remedy to control stomach acidity. It has Mg(OH)2 and Al(OH)3 as the active ingredient. See this site.
http://en.wikipedia.org/wiki/Maalox
The problem you are asking needs, before it can be answered, the concentrations of each ingredient. Since Al(OH)3 requires 3 mols acid to neutralize it and Mg(OH)2 requires just two, it makes a difference.