Learning Competency:
Investigate propertiesof acidic and basic
mixtures using natural indicators (S7MT-Ii-6)
Objectives:
1. Identify some household stuffs whether acid or
basic using a natural indicator
2. Familiarize pH level scale
3. State the uses of acid and base materials and
their importance
How Can You Tell if a
Mixture is Acidic or
Basic?
4.
1.At sea level,an odorless and colorless
Liquid A boils at a range of 1000
C to
1050
C. What inference can be drawn from
this observation?
a. Liquid A is a metal
b. Liquid A is a mixture
c. Liquid A is a non-metal
d. Liquid A is a pure substance
Review:
5.
2. Elements playan important role in the
human body. Which of the following is
correctly paired?
a. Sodium: important in nerve
conduction and fluid balance
b. Phosphorous: important in bones
and teeth and some amino acids
c. Chlorine: found outside the cells
which serves as a major electrolyte
d. Oxygen: found inside the cell
essential in the conduction of nerve
impulses
Review:
6.
What will youdo if you
experience acid reflux?
Kremil-S is an antacid that
is used for the relief of
stomach pain from
hyperacidity, gassiness,
and bloating.
7.
WORD BANK WORDBANK
ACIDS
BASE
SOUR
BITTER
LITMUS
UNLOCKING
VOCABULARY
INDICATOR
pH
NEUTRAL
ANTACID
ANTHOCYANIN
3. Which onebetween gastric
juice and tomato sauce is more
acidic? Why?
4. What is the pH value of the
human blood? How will you
compare it to the urine?
5. What have you observed
with the pH scales in terms of
acidity and basicity?
6. How does pH scale help us
when it comes to the acidity
and basicity of substances?
1. In your Math subject, how do we scale a number line?
2. Based on the Figure, what does the range from 0 – 14 indicate? How
about the pH of greater than 7,
what does it indicate?
10.
Acids - anysubstance that in water solution tastes
sour, changes blue litmus paper to red, reacts with
some metals to liberate hydrogen, reacts with
bases to form salts, and promotes chemical
reactions (acid catalysis)
Base - is a substance that can neutralize the acid
by reacting with hydrogen ions. Turns red litmus
paper to blue. Most bases are minerals that react
with acids to form water and salts. Bases include
the oxides, hydroxides and carbonates of metals.
The soluble bases are called alkalis. Sodium
hydroxide is an alkali.
Indicator – is a dye that changes into different
color depending on whether it is in acid or in
base.
There are many indicators that come from
plants. Purple mayana, Baston ni San Jose
(purple), red cabbage, Camote (purple), violet
eggplant peel are some plants that can be used as
natural indicators
11.
Natural indicators containanthocyanins that produce
specific colors in solutions.
A typical anthocyanin is red in acid, purple in neutral and
blue in basic solution.
Another indicator is the use of litmus paper. Litmus is a
dye taken from lichens (organisms that are composed of
fungi and algae). Blue litmus paper turns red in acid. Red
litmus paper turn to blue in base.
Neutral - pH only if its concentration of hydroxide and hydrogen
ions are equal to each other. pH scale of 7
But what is a pH?
In chemistry, pH, also referred to as acidity or basicity,
historically denotes "potential of hydrogen". It is a scale
used to specify the acidity or basicity of an aqueous
solution. Acidic solutions are measured to have lower pH
values than basic or alkaline solutions.
Camote
Baston ni
San Jose
Litmus paper indicator
12.
ACTIVITY
Sample Color of
Indicator
Natureof Sample
Sample may be classified using
the color scheme:
Strongly acidic: Red to pale red
Weakly acidic: blue
Weakly basic: green
Strongly basic: yellow
Calamansi strongly acidic
Tap water (from the
faucet)
weakly acidic
Distilled water neutral
Vinegar strongly acidic
Sugar in water weakly acidic (depending on
the type of water used)
Baking soda basic
Baking powder basic
Softdrink (colorless) strongly acidic
Coconut water weakly acidic
Toothpaste basic
Shampoo
Soap
basic
basic
13.
Let’s go backto the question: What do you usually intake when
you feel sour like feeling acidic and feeling vomiting?
Not all acids are dangerous but too much is. Just like anything.
Fun fact about an acid in the stomach:
“Gastric juice is made up of digestive enzymes, hydrochloric acid
and other substances that are important for absorbing nutrients –
about 3 to 4 liters of gastric juice are produced per day. The
hydrochloric acid in the gastric juice breaks down the food and the
digestive enzymes split up the proteins.”
It is not advisable to drink softdrink in an empty stomach. For
which it is the reason behind of most stomach ulcers. On the other
hand, Muslims are prohibited of non-HALAL products
14.
Generalization:
Tell whether theuses mentioned is base or acid.
1. Used in the baking industry.
2. Used in bleaching powder and used in cleaning purposes.
3. Used in personal hygiene
4. Remove grease stains from clothes
5. Use as whitewash like paints
6. Use as food preservative
7. Used in batteries
8. Used in explosives and fertilizers
9. Used in softdrinks
10.Maintenance of swimming pools