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Describe 4 properties of acidsDescribe 4 properties of bases Identify four uses of acids and bases
AcidBase Indicator
Every liquid is either an acid or a base except distilled water which in neutral
The pH scale indicates the number of Hydrogen ions to the power of 10
A solution with an excess of H+ ions
Def: any compound that increases the number of hydronium ion H30+
A solution with an excess of OH- ions when dissolved in water.
Taste sourReacts with metals such as
magnesium, zinc and iron to produce hydrogen gas H2
Turns blue Litmus paper redCause skin to burnReact with bases to form water and
chemical salt
1. Taste bitter2. Feel slippery or soapy3. Strong bases will burn skin4. Turns red Litmus paper blue
“opposite of acids”5. React with acids to form chemical
salt and water
Acid Lemon juice Orange juice Vitamin C (acetic
acid) Coca-cola Car battery
(sulfuric) Stomach acid (HCl) Carbonic acid PAGE 370
Base Milk of Magnesia Maalox Drain cleaner
(Ca2OH) Oven cleaner
(NaOH) Cleaning products
(ammonia) PAGE 373
What are some common day examples of acids that you use in your life? Bases?
When you taste a “warhead” candy, what do you taste?
Do you think electricity will like to flow through acids and bases? Why do you think this…think about the definitions…
Questions from page 373 # 2-8
pH and Neutralization
pH is an indicator that measures the amount of H+
0-6.9 is acidic7 is pure water
(neutral)7.1 and greater is
basic
The concentration of hydrogen is the key
the more hydrogen ions the lower the pH (acid) or the more acidic the solution is
The less hydrogen the higher the pH (base) or the more basic the solution is
Indicators (litmus paper) tell us if solutions are acidic or basic
Aqueous▪ A solution that is
mostly water Strong Acid
▪ pH of 0-4
Weak Acid▪ pH of 4-7
Neutral▪ pH of 7
Strong Base▪ pH of 10-14
Weak Base▪ pH of 7-10
The strength of an acid depends on its pH (number of Hydrogen ions ). A dilute solution of HCl will burn a hole in your clothes. SO THE MORE H+ that break off, the more ACIDIC THE MORE OH- that break off, the more basic
The less of H+ or OH- that breaks off, the weaker the acid/base
Neutralization
Acids in water solution separate into hydrogen ions (H+)
HCl + water H+ + Cl-Bases in water solution separate
into hydroxide ions (OH-)
NaOH + water NH4 + OH-
Neutralization A reaction between an acid and a base
is called neutralization After mixing an acid solution with a
base solution the pH of the new solution will change. Sometimes result in a neutral solution▪ Factors include, concentration, volume, and
identities
Products Salt (an ionic compound) made from the
neutralization reaction between an acid and a base
HNO3 + KOH H2O + K+ + NO3-
Some salts are soluble and remain in solution
Some salts are insoluble and precipitate In scientific terms, what are salts?
Sodium chlorideNaCl
Potassium iodideKI
Calcium chlorideCaCl2
Potassium chlorideKCl
Calcium carbonateCaCO3
Ammonium nitrateNH4NO3
Food flavoring, preservation
Additive that prevents iodine deficiency
De-icer for roads
Salt substitute in foods
Found in limestone and sea shells
Fertilizer, active ingredient in cold packs
Human Digestion HCl in stomach breaks down food (pH 2) HCO3- (bicarbonate) in small intestine
raises pH to 8 by bonding with the H+ ions enzymes of digestion work the best at pH 8
Other Human Facts Skins pH protects against being over run
by bacteria Tears are slightly acidic