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Acids & bases
❀​ph scale​= it is a measure of how acidic or alkaline a solution
...
You can also use the universal
indicator
Indicator

In acid

In alkaline

LITMUS

Red

Blue

METHYL ORANGE

Red

Yellow

PHENOLPHTHALEI
N

Colourless

Pink

● Ph probe and ph meter=​ many labs use the pH meter and probe as it
is more accurate and prevent the risk of any personal errors (doesn't
involve guessing shades)

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▩Acids:
⇨They are compounds which have ph less than 7
...
They can
eat off you skin, clothes and metals but also they have a sour taste
...
Hydrochloric acid "HCl"
2
...
Nitric acid '' HNO​3​''
4
...
Carbonic acid H​2CO
​ ​ (weak acid)
​
3
⇨Lime juice and lemon contain citric acid
Stomach contains Hydrochloric acid
Stings contain methanoic acid and fizzy drinks contain weak Carbonic
acid
⇨Acids always d
​ onate Hydrogen ions and gain electrons
⇨They turn litmus paper ​red

▩Bases:
⇨They are metal oxides and hydroxides
...
They are the same as bases but soluble
like sodium hydroxide
⇨Most common bases are=
1
...
Potassium hydroxide
3
...
Ammonia
⇨Bases always ​accept hydrogen ions and lose electrons
⇨​They turn litmus paper b
​ lue ​and taste like soap

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❀In 1923, Johannes Nicalaus
Bronsted defined first acids &
bases but Thomas Martin lowry
discovered a losing and gaining
processes in any acid base
reaction but it was the same
definition as Johannes '
❀​Bronsted-Lowry theory=
''Brønsted–Lowry theory, also
called proton theory of acids and bases, a theory, introduced
independently in 1923 by the Danish chemist Johannes Nicolaus
Brønsted and the English chemist Thomas Martin Lowry, stating that
any compound that can transfer a proton to any other compound is an
acid, and the compound that accepts the proton is a base
...

(From site Britannica
...


▩Types of acids and bases:
Types of acid

Types of base

1
...
Metal oxide
of hydrogen & a
2
...
=HCl
2
...

soluble can have group 1
ex=HNO​2
cations :)

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❀the chemist Svante August Arrhenius created a new theory that
said '' Acid is any substance that
produce H+ protons in aqueous
solutions but bases are any
substances that produces
hydroxide ions in aqueous
solution

❀Perhaps, the chemist Gilbert N
...
This always occur in
redox reactions
❀The 3 theories really helped
chemists in the equilibrium if any
equation and to compare between
acids and bases from the atomic composition
To sum up:

▩Applications that depends on bases:

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1
...

2
...

3
...

4
...

5
...
Lidocaine, a local anesthetic
used by dentists
7
...

⇨Raising the pH to alkaline state increases the ability of the immune
system to kill bacteria
⇨Alkaline body can absorb up to 20 times more oxygen than the acidic
body
⇨Symptoms of over acidic condition in the body are
● Catching cold & flu frequently
● Mouth sores, throat sore, sensitive teeth
● Always tired after an hour of desk work
...

⇨It goes out of the smoke stack then react with oxygen and water
vapour which is converted into Sulfuric acid
O
​ ​2​ + SO2​ +
​ ​O⇨2H2​ SO
​
​ H2
​
4
⇨​Results =
1
...
Acidify water supply which is threatening the aquatic life
...
Damage the soil and increase its acidity
...


⇨ When limestone reacts with Sulfuric acid from acid rains carbonic
acid and calcium sulfate precipitate is formed
...

⇨1000 kg of coal
...
03=30
kg of sulfur per ton
⇨Each ton of coal burnt by a US
power station give enough
Sulfuric acid to dissolve about 94
kg of limestone
⇨Not only in the US but also acid
rains became a tremendous
issue in 1929 for the british
power generation as in the British
house if lords ruled a power
station which was able to
damage many areas planting
crops of vegetables which really
affected the economy of many british lands
...

⇨The effect of the limestone scrubber was slightly effective as about
95 % of sulfur produced in coal-fired power station in the US is
removed before leaving the smoke stack

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