pH Value in Exposed Common Drinks
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Transcript of pH Value in Exposed Common Drinks
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pH Value In Exposed Common Drinks
INTRODUCTION
Water is an essential need by all human kind. Its a need by the body for the metabolize
process. The body will get sick if lack of water in the body and can bring death if the sickness is
too severe. The water we consume having their own unique pH value. pH value is commonly
known to determine the acidity, In the context of chemistry, In chemistry, pH is a measure of the
activity of the (solvated) hydrogen ion. pH, which measures the hydrogen ion concentration level
of a substances. Its important to know our pH value of food we consumed because its not good
for the body if the food we consume is too acidic. The acidic range for the food is 6 and less, the
value for the alkali is 8 and more. The natural value for the natural substances is exactly 7.
The pH of the drinks may vary accordingly to the time changes. Especially when the
drinks were exposed for a long time of period and the pH will absolutely changes. This
experiment was focusing on the changes of the pH of the drink after got exposed for a long time
of period or the changes of pH in the good condition drink and after the drinks got expired, the
period we choose is a week. In this experiment, we are taking 5 different drinks which are coke,
milk, and apple juice, black coffee and lemon tea. We taking these 5 different drinks because
these drinks are common drinks consumed by most of the peoples.
Every drinks react differently to the exposed air. This is because the content of the
drinks are differently for each drinks. To be beginning with, every drink we choose has initiallydifferent pH. The initial pH for coke is 2.61, initial pH for milk is 6.76, initial pH for apple juice
3.49, the initial pH for black coffee is 5.51, and lastly the pH for the initial of lemon tea is 3.73.
As we can see, the most acidic drink in the drink samples we take is coke which is 2.61 and the
highest value of the pH is 6.76 which is the milk that almost to the natural value that is 7.
The initial pH of the coke is the lowest and shows that that it is the unhealthiest drink
from all these 5 drinks. It is also classified as the soft drink which is common to people now a
days. DrDAQ is used here as a pH meter with the addition of a pH probe to measure the pH;
level over the entire pH scale of a range of common drinks. Recently dentists have begun
warning about the dangers of drinking acidic drinks. Teenagers, they suggest, who drink large
amounts of fizzy pop drinks suffer from tooth erosion whereby the enamel covering of the tooth
is dissolved by the acid in the drink. Athletes are also at risk from drinking sports drinks. The
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recommended safe level for the pH of drinks is 5.5; anything below this can promote tooth
erosion.
This experiment looks at the relative pH values of different drinks and can be used to
determine whether a particular drink is safe according to the above criteria. It can also be used
as a good introduction to further studies into tooth decay and enamel stripping. It is suitable for
ages 14+ and requires some knowledge of the pH measurement. PH is very important in the
control of number of water and waste water treatment processes and in the control of corrosion.
"PH" value is the measure of concentration of hydrogen in water it shows the alkanity or
acidity of water. Mathematically PH may be defined as:
The negative log of hydrogen ion concentration
PH= - log [H]
Sorenson in 1909 introduced this scale for the first time.
H20 H4 + OH
This reaction shows that the number of H4 and OH ions are equal experimentally it has been
proved that the product of concentration of H4 and OH is a constant quality K, whose value was
found to be 1 14.
ENGAGE
Engage is a step that to create a problem statements. Actually, the problem statements that
created by the observation to the surrounding. Our groups chooses Do the pH value of
common drinks will changes when the food are exposed to environment in long period of time?
as our problem statements because our groups member wonder that what happen to the pH
and composition of drinks when it exposed to surrounding in a long period of time.
EMPOWER
Empower is a step in data logging which need to planning and doing the experiments.
Title : pH Value in Exposed Common Drinks
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Objective
1. To know the pH of common drinks when exposed to surrounding in long period of time.
Hypothesis
pH value of common drinks will change when exposed to surrounding.
Equipment required
I. DrDAQ data logger connected to a PC
II. One pH sensor (DrDAQ Part no DD011)
III. Containers for the drinks (we used plastic drinking cups)
IV. A selection of common drinks - we used:
Apple Juice
Black Coffee
Lemon Tea
Original Coke
Milk
Procedures
1) Take 50 ml of liquid sample 1.
2) Gently agitate the pH probe in each liquid for a minute or two while the pH reading
settles then record the reading in the table A.
3) Then, the liquid leaves for a week.
4) The experiment is repeat for each other drinks water sample.
NOTE: Take care to thoroughly clean the pH probe in a large container of water
between each liquid to reduce cross contamination of the liquids.
5) After a week, the pH of the liquids is taken.
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Results
Food Sample pH pH (after a week)
Coke 2.61 2.24
Milk 6.76 4.40
Apples juice 3.49 1.84
Black coffee 5.51 5.42
Lemon tea 3.73 2.65
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Discussions
pH is a measure of how acidic or alkaline a solution in water is. The pH scale is numbered
between 0 and 14.
a) If a solution has pH below 7, it is acidic.
b) If a solution has pH of 7, it is neutral.
c) If a solution has pH above 7, it is alkaline.
There are two common methods to determine the pH of a solution.
i) By using universal indicator
ii) pH meter
0
2
4
6
8
Graph of pH Before vs pH After a Week
pH
pH (after a week)
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Based on the table above, the pH value of the exposed food after 1 week exposed to the
environment in decrease from its original value. For examples, the initial pH value of coke is
2.61, then after 1 week the pH value of coke is 2.24. It decreases about 0.37. The initial pH
value of milk is 6.76, then after 1 week the pH value of milk is 4.40. It decreases about 2.36.
The initial pH value of apples juice is 3.49, then after 1 week the pH value of apples juice is1.84. It decreases about 1.65. The initial pH value of black coffee is 5.51 then after 1 week the
pH value of black coffee is 5.42. It decreases about 0.09. Lastly, the initial pH value of lemon
tea is 3.73, then after 1 week the pH value of lemon tea is 2.65. It decreases about 1.08.
Generally; the drink samples have pH value below 7 that mean they are acidic drinks. After
1 week, they are became more acidic that before. These changes may occur by the outer factor.
Windblown dust, debris, and contaminants brought in by bathers may cause sudden changes in
pH. Therefore the temperatures of environment also affect the pH value in drinks. The liquids
sample was contaminated by bacteria or others at surrounding. There is some problem drink
that effected.
There are tooth decay and dental erosion. Tooth decay is the process that results in a cavity
(dental caries). It occurs when bacteria in your mouth make acids that eat away at a tooth. If not
treated, tooth decay can cause pain, infection, and tooth loss. It easily prevents tooth decay by
brushing and flossing your teeth regularly, seeing a dentist for teeth cleaning and checkups, and
avoiding foods those are high in sugar. The combination of bacteria and food causes tooth
decay. A clear, sticky substance called plaque that contains bacteria is always forming on your teeth and gums. As the bacteria feed on the sugars in the food you eat, they make acids. The
acids attack the teeth for 20 minutes or more after eating. Over a period of time, these acids
destroy tooth enamel, resulting in tooth decay. Tooth decay usually does not cause symptoms
until you have a cavity or an infected tooth. When this occurs, a toothache is the most common
symptom. A dentist diagnoses tooth decay by:
Asking questions about your past dental and medical problems and care.
Examining your teeth, using a pointed tool and a small mirror.
Taking X-rays of your teeth and mouth.
Treatment for tooth decay depends on how bad it is. You may be able to reverse slight tooth
decay by using fluoride. To fix cavities caused by mild tooth decay, your dentist will fill the
cavities with another substance (fillings). For more severe tooth decay, you may need a crown
or root canal. In extreme cases, your dentist may have to remove the tooth.
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Erosion is the loss of tooth enamel caused by acid attack. Enamel is the hard, protective
coating of the tooth, which protects the sensitive dentine underneath. When the enamel is worn
away, the dentine underneath is exposed, which may lead to pain and sensitivity. Erosion
usually shows up as hollows in the teeth and a general wearing away of the tooth surface and
biting edges. This can expose the dentine underneath, which is a darker, yellower color than theenamel. Because the dentine is sensitive, your teeth can also be more sensitive to heat and
cold or acidic foods and drinks.
Every time you eat or drink anything acidic, the enamel on your teeth becomes softer for a
short while, and loses some of its mineral content. Your saliva will slowly cancel out this acidity
in your mouth and get it back to its natural balance. However, if this acid attack happens too
often, your mouth does not have a chance to repair itself and tiny particles of enamel can be
brushed away. Over time, you start to lose the surface of your teeth. Bulimia is a condition
where patients make themselves sick so that they lose weight. Because there are high levels of
acid in the vomit, this can cause damage to tooth enamel. Acids produced by the stomach can
come up into the mouth (this is called gastro-esophageal reflux). People suffering from hiatus
hernia or esophageal problems, or who drink too much alcohol, may also find they suffer from
dental erosion due to vomiting.
Acidic foods and drinks can cause erosion . Acidity is measured by its pH value', and
anything that has a pH value lower than 5.5 is more acidic and can harm your teeth. Fizzy
drinks can cause erosion. It is important to remember that even the diet brands are still harmful.Even flavored fizzy waters can have an effect if taken in large amounts, as they contain weak
acids which can harm your teeth. Acidic foods and drinks such as fruit and fruit juices,
particularly citrus ones including lemon and orange, contain natural acids which can be harmful
to your teeth, especially if you have a lot of them often. Alcopop' drinks that contain acidic fruits
and are fizzy can cause erosion too. Still water is the best drink for teeth, and milk is also good
because it helps to neutralize the acids in your mouth.
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Questions
The formula for pH is:
1. With respect to the results you have obtained, can you make any predictions about thelikely pH values of the foods and drinks we consume?
We can predict that the pH of the majority of our foods and drinks will be neutral or
acidic.
2. Find the pH of a solution whose is 9.5E-8M?
pH=7.02
3. Was the milk acidic or basic?
Milk can be slightly basic or slightly acidic depending on its age and how it was
processed at the dairy.
4. How does the pH reading of a liquid vary with temperature? (Possibly heat a buffer
solution)
5. How you would calibrate the pH probe?
Conclusions
a. The hypothesis was accepted.
b. The pH of all liquid samples was changes although in small amount of changes.
c. Many factors that can make the pH of liquids sample changes for example temperature.d. Maybe the liquids sample was contaminated by bacteria or others at surrounding.
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ENHANCE
Enhance is an application for the experiments. The application for pH value is play an important
role in our daily life. The application for this experiment is to determining tooth decay and dental
erosion. Dental erosion occurs when tooth enamel (and dentine) are destroyed by the action of
acid on teeth. This is a different process to the damage caused by acid from decay producing
bacteria. Unlike tooth decay, erosion affects the whole surface of the tooth. Exposure to acid
over a long period of time leads to progressive loss of enamel with the effect that the tooth
shrinks and crumbles at the biting edge. Eventually t he dentine is exposed leading to pain and
sometimes death of the tooth. Several common drinks fall below the safe recommended pH
level of 5.5. In order to minimize damage the following dental recommendation should be
followed.
Examples of Dental Erosion