Analyzing Antacids Science 10

Background Information Chemical reactions change the food you eat into compounds that your body uses to grow, maintain & repair cells & tissues & provide energy. These reactions are collectively known as digestion. The stomach is one of several organs involves in digestion.

Stomach

The stomach secretes an acid that helps break down food particles. This acid can cause a condition called heart burn / acid indigestion. It occurs when the stomach contents are pushed into the lower area of the esophagus The esophagus does not have a protective lining like the stomach, so you feel a burning sensation in your throat & chest

Creating an Experiment In this investigation, you and your partner will study one aspect of antacids Formulate a question based on information you have studies in this unit Then decide how you will carry out an experiment to answer your question

Think about it ! Go to page 132 – 133 in your science 10 text book to look at some suggested areas and methods of this investigation

By the End of Class I Must See: Introduction Hypothesis/Prediction Step by step procedure with diagram Data / observation section (creation of a table?)

Materials available to you: 150 mL beakers Bromothymol blue HCl (5-10 mL limit of HCl per antacid) Sodium bicarbonate (used to neutralize HCl) pH paper pH meter Weigh boats Antacids (Rolaids, Tums, Pepto bismol, Maalox, Alka-selter)

About materials: Do NOT exceed 10 mL of HCl per antacid tablet Rule of thumb: 100mg of antacid = 1mL of HCl Take only 1 antacid tablet per use Use beakers to mix acid/base with antacid Use granulated cylinders for measuring ONLY Use HCl to neutralize the antacid (to reduce amount of HCl used)

Possible investigation questions: Does a neutralization reaction take place? If so, how can you use indicators to compare effectiveness of active ingredients in antacids? How do antacid tablets of different brands compare in terms of neutralizing ability? What does this have to do with mass of the tablet or active ingredient? What are the products of the reaction between an antacid and an acid?

Things to think about: Will you need to weigh your antacid? Will you need the same amount of HCl or sodium bicarbonate? How will you measure the pH?