Science Buddies: "Ask an Expert"

Hi-
I've found two antacid science fair project ideas that I'm interested in, but I was hoping to modify them because I believe they might be too simple for a high school level science project.
One was comparing different liquid antacid's ability to neutralize lemon juice by using a mixture of grape juice and lemon juice and then recording the amount of drops of antacid it would take to neutralize the mixture. (The mixture would change color when neutralized)
The other one was from Science buddies (https://www.sciencebuddies.org/science- ... #procedure), where you create artificial stomach acid and add in an antacid until the pH is neutral.

If anyone has any ideas for modifying these projects to make them a bit more advanced and so I don't necessarily have to 'copy' the projects, that would be much appreciated.

thank you!

mjlanddeck - No experiment has to be too simple. You can make an elegant experiment by writing a very comprehensive hypothesis, describe your approach clearly, follow precise procedures, control all variables, keeping accurate notes and measurements and writing up your results. I would tend to use the Science Buddies approach as I'm not sure what the contents of the grape juice are and how it may alter results. Also, lemon juice as the acid element may vary from lemon to lemon and not give you an accurate baseline. The Science Buddies experiment uses Hydrochloric acid (easily obtainable at hardware or pool supply stores) and will allow you to create a very specific acid, almost reagent grade acid mixture. Good luck on your experiment. Caution, use rubber or nitrile gloves and eye protection when handling acid. Always add the acid slowly to any water used, not the other way around. Adding water to acid can result in violent thermal reaction and splattering.

Rick Marz

Thanks for the advice and precautions! Those are definitely important tips to take note of.

Also, in the procedure of the experiment it uses a TUMS tablet. Would it be okay/safe to use liquid antacids or should it be tablets?

mjlandeck - The choice of antiacids to use is really part of your experiment and hypothesis. What are you trying to verify? Effectiveness of dosages, speed at which neutralization occurs, cost of products? Liquid, tablet or powder may not be an important factor in your experiment.

Rick Marz

I was just wondering if it would make any difference if I used antacids in liquid form or tablet form.

Hi mjlandeck,

To first order, the reaction you observe will be limited by the amount of anti-acid compound available. If the liquid and tablet forms have the same amount of active ingredient(s), then, to first order, they should give similar results. However, the inactive ingredients in the liquid and tablet form are probably different, and these inactive ingredients might also affect the reaction. I suggest choosing one form (either liquid or tablet) and sticking with it. Alternatively, you could make liquid vs. tablet your independent variable and explore any differences between the way the two react.