Transcript acid

Chapter 25
Acids, Bases, and Salts
Section 1-Acids and Bases
 An
acid is a substance that produces
hydrogen ions in a water solution.
 The ability to produce ions is what
gives their characteristic properties.
 When an acid dissolves in water, H⁺
ions interact with water molecules to
form H₃0⁺ ions, which are called
hydronium ions.
Properties of Acids
 Citric
Acid is found in citrus fruits.
 Lactic Acid is found in yogurt and
buttermilk.
 Vinegar is also known as acetic acid.
 Your stomach uses hydrochloric acid
to help you digest your food.
Common Acids
Name, Formula
Use
Other Information
Acetic Acid
Food Prep and Preservation
When in solution with water
it is known as vinegar
Acetylsalicyclic Acid
Pain Reliever, Fever reducer
Known as aspirin
Ascorbic Acid
Antioxidant, Vitamin
Called Vitamin C
Carbonic Acid
Carbonated Drinks
Involved in cave, stalactite,
and stalagmite formation
and acid rain
Hydrochloric Acid
Digestion as gastric juice
Commonly called Mariatic
Acid
Phosphoric Acid
Makes detergents, fertilizers,
and soft drinks
Sour but pleasant taste,
detergents containing
phosphates polute water
Sulfuric Acid
Car batteries, fertilizers
Dehydrating agent, causes
burns by removing water
from cells
Nitric Acid
Makes fertilizers
Colorless, but yellow when
exposed to light
Common Acids
A
substance that forms hydroxide
ions, OH⁻, in a water solution is a
base.
 A base is also any solution that
accepts H⁺ from acids.
 Think of bases as the opposite of
acids.
Properties of Bases
In pure and undissolved state many bases
are crystalline solids.
 In a solution bases feel slippery and have
a bitter taste.
 Strong bases are like strong acids as they
are corrosive and can burn the skin.

Properties of Bases
Name, Formula
Use
Other information
Aluminum Hydroxide
Color-fast fabrics, antacid,
water purification
Sticky gel that collects clay
ad dirt particles on surface
Calcium Hydroxide
Leather-making, mortar
and plaster, lessen acidity
of soil
Called caustic lime
Magnesium Hydroxide
Laxative, antacid
Called milk of magnesia
Sodium Hydroxide
To make soap, oven
cleaner, drain cleaner,
textiles, and paper
Called lye and caustic
soda; generates heat when
combined with water,
reacts with metals to form
hydrogen
Ammonia
Cleaners, fertilizer, to make
rayon and nylon
Irritating odor that is
damaging to nasal
passages and lungs
Common Bases
Ammonia is a popular household cleaner.
 Never combine products containing
ammonia with other cleaners that contain
chlorine such as toilet bowl cleaners and
bleach. The reaction produces poisonous
gases.
 Solutions of both acids and based produce
some ions that are capable of carrying
electric current to some extent. They are
considered to be conductors.

Acids & Bases
Chapter 25
Acids, Bases, and Salts
Section 2- Strengths of Acids and Bases
The strength of an acid or base depends
on how completely a compound separates
into ions when dissolved in water.
 An Acid that ionizes almost completely in
solution is a Strong Acid.
ex. Hydrochloric Acid
 A weak acid is an acid that only partly
ionizes in a solution.
Ex. Acetic and Carbonic Acids

Strong Acids and Weak Bases
The pH of a solution is a measure of the
concentration of H⁺ ions in it.
 The greater the H⁺ concentration is, the
lower the pH is and the more acidic the
solution is.
 The pH measures how acid or basic a
solution is.

pH

To indicate pH, a scale ranging from 0 to
14 has been devised.
pH
Solutions with a pH lower than 7 are
described as acidic.
 Solutions with a pH greater than 7 are
described as basic.
 A pH of exactly 7 indicates that the
concentration of H⁺ ions and OH⁻ ions are
equal. These solutions are neutral.
Ex. Pure water at 25 degrees has a pH of
7.

pH

One way to determine pH is by using pH
indicator strips. The final color of the pH
paper is matched with colors on a chart to
find the pH.
pH
The blood that circulates through your
body has a pH of between 7.0 and 7.8
 Your body can not work outside of this pH
range.


Does your Blood pH change when you eat
spicy/acidic foods?
Blood pH
You would think that your pH in your
blood changes when you eat spicy/acidic
foods but it does not.
 Your blood contains compounds called
Buffers that enable small amounts of
acids or bases to absorbed.
 Buffers are solution containing ions that
react with additional acids or bases to
minimize their effects on pH.

Blood pH
Chapter 25
Acids, Bases, and Salts
Section 3-Salts
Neutralization is a chemical reaction
between an acid and a base that takes
place in a water solution.
 Antacid Tablets are an example of a
product that a person suffering from
indigestion cant take to “neutralize” the
effects of acid reflux.

Neutralization

A salt is a compound formed when the
negative ions from an acid combine with
the positive ions from a base.
Name
Common Name
Uses
Sodium Chloride
Salt
Food Prep
Sodium Hydrogen
Carbonate
Sodium bicarbonate
baking soda
Food Prep and
antacids
Calcium Carbonate
Calcite, Chalk
Making paint and tires
Potassium Nitrate
Saltpeter
Fertilizers
Potassium Carbonte
Potash
Making soap and glass
Sodium Phosphate
TSP
Detergents
Ammonium Chloride
Sal ammoniac
Dry-Cell Batteries

If you need to know the concentration of
an acid or base in a solution you can
determine it through a process called
titration.
Titration