2. How Can You Tell If A Mixture Is
Acidic or Basic?
• You will distinguish acidic and basic mixtures based
on their color reactions to an indicator.
• An indicator is a dye that changes into a different
color depending on whether it is in acid or in base.
• A common indicator is litmus, a dye taken from
lichens. It can be red or blue. The color of red litmus
paper remains the same under acidic conditions and
turns blue under basic conditions.
3. Part A. Preparation of Indicator
Materials needed:
• 1 pc mature dark violet eggplant
• Alum (tawas) powder
• Peeler
• Milk can
• Bottle with cover
• Alcohol lamp
• Tripod
4. Part B. Determining the acidity or basicity of
some common household items
Materials needed:
• Plant indicator prepared
in Part A
• Vinegar
• Tap water
• Calamansi
• Toothpaste
• Shampoo
• 5 small plastic cups
• 5 plastic teaspoons
• Stirrer
5. strongly acidic red to pale red
weakly acidic blue
weakly basic green
strongly basic yellow
6. What Happens When Acids
And Bases Combine?
• You will find a pH value that is not acidic or
basic. Mixtures that are not acidic or basic is
called neutral.
• When an acid mixed with bases, water and salt
are produced. Such process is called
neutralization.
7. • If a basic mixture is added to an acidic mixture, the
resulting mixture will no longer have the properties
of the acidic mixture.
• If acidic mixture is added to a basic mixture, the
properties of the basic mixture are changed.
• The acid and the base in each mixtures neutralize
each other to produce a mixture with a different
set of properties.
8. SUMMARY:
• An acid is a substance whose water solution exhibits the
following properties: turns litmus paper red, has a sour
taste, neutralizes bases and reacts with active metals to
produce hydrogen gas.
• A base is a substance whose water solution turns litmus
paper blue, has a bitter taste, biting taste, has a slippery,
soapy feeling and neutralizes acids.
• Plant indicators are used to determine the acidity or
basicity of common household items.
9. SUMMARY:
• Neutralization is a process in which base is mixed with
an acid to produce salt.
• There are known natural indicators extracted from red
cabbage, roses, camote tops, red apple skin, red onion,
tomato, pandan leaves, and avocado seeds.
• Common examples of bases are as follows: sodium
hydroxide, baking soda, detergent, ammonia, and bleach
ing powder.
10. SUMMARY:
• Common examples of acids are as follows: kalamansi,
vinegar, carbonated drinks, orange, tomato, and
hydrochloric acid.
• As the pH value increases, the acidic character of
substances decreases and its basic character increases.
• As the pH value decreases, the acidic character of
substances increases and its basic character decreases.
Editor's Notes
Whenever there is an interaction between two objects, there is a force upon each of the objects
This means that a force can be described in terms of what it does
However, forces do not always cause motion. It does not necessarily follow that forces acting on an object will always cause it to move.
