Transcript ACID - s3.amazonaws.com

Sour in taste
Produce H+ (hydrogen ions)
Turns blue litmus red
Acids + metals
salt + hydrogen gas
Conduct electricity
are corrosive (acid rain)
Acid + base
salt + water (neutralization)
pH less than 7
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HCl - hydrochloric- stomach acid
H2SO4- sulfuric acid - car batteries
HNO3 - nitric acid - explosives
HC2H3O2- acetic acid - vinegar
H2CO3-carbonic acid - sodas
H3PO4- phosphoric acid - flavorings
Examples of acids:
• Vinegar
• Lemon Juice
• Soft Drink
• Battery Acid
• Stomach Acid
• Apple Juice
• Black Tea
 Weak Bases: ammonia; potassium
carbonate, sodium carbonate
 Strong Bases: sodium hydroxide; sodium
phosphate; barium hydroxide; calcium
hydroxide
Bitter to taste
Soapy to touch
Water soluble bases are called alkalies
All alkalies are bases but all bases are not
alkalies
Turns red litmus blue, phenolphthalein pink
and methyl orange yellow
Base + acid
salt + water
pH greater than 7
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NaOH- sodium hydroxide (LYE) soaps, drain cleaner
Mg (OH)2 - magnesium hydroxide-antacids
Al(OH)3-aluminum hydroxide-antacids, deodorants
NH4OH-ammonium hydroxide- “ammonia”
Examples of bases:
• Detergent
• Baking Soda
• Drain Cleaner
• Ammonia
• Soaps (hand, dish)
• Antacid
• Weak Bases: ammonia; potassium
carbonate, sodium carbonate
• Strong Bases: sodium hydroxide; sodium
phosphate; barium hydroxide; calcium
hydroxide
• These are items that are neither acids or
bases.
• Neutral items will turn blue and red litmus
paper green.
• The main example of a neutral item is:
Pure Water
Indicator
Acid
color
Neutral
color
Base
color
Phenolphthalein Colorless Faint pink Dark pink
Bromthymol
blue
Yellow
Green
Blue
Litmus
Red
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Blue
• Red litmus paper
• Blue litmus paper
• pH
• Red Cabbage Juice
•Robert Boyle discovered litmus paper
•certain plant extracts, such as litmus, can be
used to distinguish acids from bases.
• blue and red litmus paper turn red when
dipped in an acid
• red and blue litmus paper turn blue when
exposed to a base
the negative logarithm of the
hydronium ion concentration of
an aqueous solution; used to
express acidity.
• pH is the measure of the acidity or
basicity of a solution.
• The pH scale ranges from 1 to 14
• 1 through 6 being acidic
• 7 is considered neutral
• 8 through 14 being basic
• red cabbage can be used as an acid/base
indicator
• after boiling the red cabbage, pour a small
amount of the juice into a small sample of a
substance your checking
• the juice will turn blue if the substance is a
base
• the juice will turn red if the substance is an
acid
• A salt is a neutral substance produced from the
reaction of an acid and a base.
• Composed of the negative ion of an acid and the
positive ion of a base.
• One of the products of a Neutralization Reaction
• Examples: KCl, MgSO4, Na3PO4
• A neutralization reaction is the reaction of
an acid with a base to produce salt and
water.
• Example
H2SO4 + NaOH  NaHSO4 + H2O
• Digestion-process by which foods are broken down
into simpler substances.
• Mechanical digestion-physical process in which food is
torn apart (mouth)
• Chemical digestion- chemical reactions in which large
molecules are broken down into smaller molecules.
(stomach and small intestines)
• Mouth-pH around 7. Saliva contains amylase,
an enzyme which begins to break
carbohydrates into sugars.
• Stomach- pH around 2. Proteins are broken
down into amino acids by the enzyme pepsin.
• Small intestine-pH around 8. Most digestion
ends. Small molecules move to bloodstream
toward cells that use them
• ACID - A class of compounds whose water solutions taste
sour, turn blue litmus to red, and react with bases to form salts.
• BASE - A class of compounds that taste bitter, feel slippery in
water solution, turn red litmus to blue, and react with acids to
form salts.
• NEUTRAL - These are items that are neither acids or bases.
There are 4 main ways to determine if a substance is and acid
or a base. They are: Red litmus paper, Blue litmus paper, pH,
and Red Cabbage Juice.