Antacids Neutralize Acid (DOC)

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					                                      Acid-Base Neutralization

Acids and bases react together to form salt and water. When acids and bases react together and
use each other up completely, we are left with a neutral product.

The reaction between acids and bases is called neutralization. Neutralization is a kind of double
displacement reaction. Write the balanced chemical equation for the reaction between
hydrochloric acid and sodium hydroxide.

                                      Comparison of Antacids

Antacids neutralize excess acids in the stomach. They do not generally use up all the acid in the
stomach, but they use up some of the acid and ease the discomfort.

       I wonder which antacid neutralizes the most acid. That could be pretty useful info! Follow
        the procedure below to compare three antacids.

    1. Set up a buret on a stand. Fill the buret with 0.5M HCl. Record the initial volume of acid in
       the buret.
    2. Measure the mass of an antacid tablet. Crush it and place it in a beaker.
    3. Add 3 drops of bromthymol blue (BTB) to the antacid in the beaker and place beaker on a
       piece of white paper. Recall that BTB turns yellow in acid.
    4. As you add acid to the antacid, the two will react. When all of the antacid has reacted,
       adding more acid will make the contents of the beaker acid. The pH indicator will then
       make a permanent colour change. Add acid from the buret to the antacid mixture. Swirl to
       mix. Continue to add acid until the pink colour has just disappeared.
    5. Record the final volume of the acid. Determine the amount of acid neutralized by the
    6. Repeat for two other types of antacids.

                            Mass of         Final         Initial     Volume of     Volume of Acid
                            Antacid       Volume of     Volume of        Acid       Neutralized per
                             Tab            Acid           Acid       Neutralized    g of antacid
                              (g)           (mL)           (mL)         (mL)            (mL/g)

Which is the best antacid? Why?

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