3.0 PART 2

Topic : Universal indicator experiment (acid and base)

Purpose : To determine the acidity and alkalinity of the products that we used

in our life daily.

Theory : Universal indicator used to determine the acidic and alkalinity of the

products by observe the colour change of indicator. Universal

indicator solution or paper, is prepared from mixing several indicators

to give a variety of colours to match the pH. It is a very handy indicator

for showing whether the solution is very weakly/strongly acidic (pH

<7) or alkaline (pH >7) or neutral (pH = 7) and gives the pH to the

nearest pH unit. Acids are substances which produce hydrogen ions in

solution. Bases are substances which produce hydroxide ions in

solution. The pH scale ranges from 0 to 14. Substances with a pH

between 0 and less than 7 are acids pH and H+ are inversely related

lower pH means higher H+. Substances with a pH greater than 7 and

up to 14 are bases higher pH means lower H+. Right in the middle, at

pH = 7, are neutral substances, for example, pure water. The

relationship between H+ and pH is shown in the table below alongside

some common examples of acids and bases in everyday life. If the

blue Litmus paper turns red the red is unaffected  then the substance is

acidic. If the red Litmus paper turns blue  the blue is unaffected  then

the substance is alkaline.If neither red nor the blue paper changes

colour, the substance is neutral.

Apparatus and materials:

I. Eye protection

II. White tile

III. Dropper

IV. Universal indicator

V. pH scale

VI. Blue and red litmus paper

VII. Softlan

VIII. Toothpaste

IX. Facial wash

X. Soy sauce

XI. Nail remover

XII. Body lotion

XIII. Shampoo

XIV. Dish wash

XV. Full cream milk

XVI. Detergent

Procedure :

1) The samples of each and every products were placed on the white tile.

2)  The red litmus paper was immersed into the all the samples to be tested.

Thus , this method was repeated by using blue litmus paper.

3) The colour changes of the samples was observed by using universal indicator

and by refering pH scale .

4) All the observation were recorded and plotted as a table. The pieces of litmus

paper were disposed in a waste bin.

Results:

Products Observation

Universal

indicator, pH

scale, litmus

paper,(acid/alkali)

Effects of the

product

1)Toothpaste

The

indicator

change

colour into

blue.

pH scale is

10.0

red litmus

paper turns

into blue.

Alkali

High pH of the

toothpaste

helps to kill any

bacteria that

reside in your

mouth at the

time of

brushing.

Those bacteria

prefer a neutral

to slightly acidic

environment,

exactly the

conditions of

your unbrushed

mouth.

Toothpastes

are ideal as

temporary relief

of skin burns

because too

alkaline.

Products Observation

Universal

indicator, pH

scale, litmus

paper,(acid/alkali)

Effects of the

product

2) Softlan

The

indicator

change

colour into

orange.

pH scale is

4.0

Blue litmus

paper turns

into red.

Acid

Used to soften

fabrics and

has

remarkable

disinfecting

qualities

because it has

low pH scale.

Can cause

skin irritating

because its

acidic.

Non-

environment

friendly

because it is

too acidic can

harmed plants

and aquatic

living things if

poured into it.

Products Observation

Universal

indicator, pH

scale, litmus

paper,(acid/alkali)

Effects of the

product

3) Full cream

milk

The

indicator

change

colour into

yellow.

pH scale is

6.0

Blue litmus

paper turns

into red.

Acid

Lactic acid

found in milk

plays main role

to prevent

tooth decay.

It makes

healthy bones

and tooths.

Milk providing

the amino

acids for lack

of proteins in

our body.

If we drink milk

every day

never affect

our body

because it is a

weak acid.

Universal

Products Observation

indicator, pH

scale, litmus

paper,(acid/alkali)

Effects of the

product

4)Nail remover

The

indicator

change

colour into

orange.

pH scale is

4.0

Blue litmus

paper turns

into red.

Acid

The acidic properties

of the nair remover

can :

Dehydrate the

skin.

Cause

irritation to

eyes.

Make nails dry

and brittle.

 Have distinct

chemical smell

and are highly

flammable.

Contains

acetone and

highly volatile.

Harm any

plant it is

applied to. As

well as

yourself if

ingested or

inhaled .

Universal

Products Observation

indicator, pH

scale, litmus

paper,(acid/alkali)

Effects of the

product

5)Facial wash

The

indicator

change

colour into

blue.

pH scale is

10.0

Red litmus

paper turns

into blue.

Alkali

It can preserve

the nature

moisture of the

skin because it

has soapy

effect because

of strong alkali.

This cleanser

have high

levels of PH

can last longer

on our skin

can cause

irritation and

skin problems.

It is important

to try to pick a

cleanser that is

about 5.5.

This will help

maintain the

skin’s acidity

and keep

everything

balanced.

Universal

Products Observation

indicator, pH

scale, litmus

paper,(acid/alkali)

Effects of the

product

5) Soy

souce

The

indicator

change

colour into

orange.

pH scale is

4.0

Blue litmus

paper turns

into red.

Acid

High intake of

the soy source

may cause

health problem

such as heart

disease,high

blood

pressure,

stomach ache

because its too

acidic and

salthy.

No nutritional

value at all

Cause allergic

reaction for

some kind of

the skins

because it too

acidic and

unbalanced for

our body.

Universal

Products Observation

indicator, pH

scale, litmus

paper,(acid/alkali)

Effects of the

product

7) Dish wash

The

indicator

change

colour into

blue.

pH scale is

14.0

red litmus

paper turns

into blue.

Alkali

It removes all

the food

particles,bacte

ria,germs that

stick on dishes

properly

because

contain high

level of pH

level.

Phosphates

that contain in

dish wash is a

strong alkali

can cause

algae growth

in freshwater,

threatening

aquatic and

plant life.

Kill some plant

cause skin

irritation

because of

strong alkali.

Products Observation

Universal

indicator, pH

scale, litmus Effects of the

paper,(acid/alkali) product

8) Body lotion

The

indicator

change

colour into

green.

pH scale is

8.0

Red litmus

paper turns

into blue.

Alkali

Useful for our

skin because

of the

softening and

moisturizing

effect because

strong alkali.

Its better

alkalize our

body skin

because our

skin is acidic

too keep

balanced we

have to

choose the

product with a

perfect pH

range.

Environment

friendly.

Products Observation

Universal

indicator, pH

scale, litmus Effects of the

paper,(acid/alkali) product

9)Detergent

The

indicator

change

colour into

blue.

pH scale is

10.0

Red litmus

paper turns

into blue.

Alkali

The high level of Ph

can cause:

Non-

environment

friendly.

can lead to

freshwater

algal blooms

that

releases toxin

sand deplete

oxygen in

waterways.

destroy the

external

mucus layers

that protect the

fish from

bacteria and

parasites.

Most fish will

die when

detergent

concentrations

approach 15

parts per

million.

decreasing the

breeding ability

of aquatic

organisms.

Cause irritation

of skins so

better wear

gloves when

awash clothes.

Harmed to

plants.

Products Observation

Universal

indicator, pH

scale, litmus

paper,(acid/alkali)

Effects of the

product

10) Shampoo

The

indicator

change

colour into

orange.

pH scale is

5.0

Blue litmus

paper turns

into red.

Acid

Acidic medium

in shampoo

help dissolve

soap scum

and to make

your hair

smooth.

We better

used the

shampoo of

the pH

balanced in

range 5.0 -5.5

to keep our

hair healthy.

Harmed plants

and aquatic

living things

because too

acidic.

Too acidic can

cause irritating

to our skin.