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Learning Objectives Define acid and base according to Bronsted-Lowry
theory List the general characteristics of acids and bases. Name common binary acids and oxyacids given
their chemical formulas Define the terms solute, solvent, solution, solubility
and molarity Calculate molarity
ACIDS
Have you ever had a muscle cramp after working out?
This is a result of lactic acid building up in your muscles when oxygen is limited.
What is an acid? An acid is a substance that
produceds H+ ions in water.
According to the Bronsted-Lowry theory an acid is a proton donor
It comes from the Latin word acidus that means "sharp" or "sour".
The more H+ ions, the more acidic the solution.
Define acid and base according to Bronsted-Lowry theory
Properties of Acids
Tastes Sour Conduct Electricity Corrosive, which means
they break down certain substances. Many acids can corrode fabric, skin, and paper
Some acids react strongly with metals
Turns blue litmus paper red pH below 7
Picture from BBC Revision Bites http://www.bbc.co.uk/schools/ks3bitesize/science/chemistry/acids_bases_1.shtml
List the general characteristics of acids and bases.
Some Common Uses of Acids Acetic Acid = Vinegar Citric Acid = lemons, limes, & oranges. It
is in many sour candies such as lemonhead & sour patch.
Ascorbic acid = Vitamin C which your body needs to function.
Sulfuric acid is used in the production of fertilizers, steel, paints, and plastics.
Lactic acid is also produced by bacteria in milk – this is why milk turns sour.
Insects such as millipedes, scorpions, and ants use acids to deter predators.
Naming AcidsChemical Formula
Chemical NameBinary Acids• Named by
anion• Starts with
hydro-• Anion name
ending in –ic• Add the word
acid
HCl Hydrochloric Acid
HF Hydrofluoric Acid
H2S Hydrosulfuric Acid
HBr Hydrobromic Acid
H3P Hydrophosphoric Acid
HI Hydroiodic Acid
Name common binary acids and oxyacids given their chemical formulas
Naming AcidsOxyacids
• These acids contain polyatomic ions (and therefore usually contain O atoms)
• Based on the polyatomic anion bonded to hydrogen
• If polyatomic ion is –ite then acid is –ous• If polyatomic ion is –ate then acid is -ic
Name common binary acids and oxyacids given their chemical formulas
Naming AcidsChemical Formula
Polyatomic Ion Name of Acid
HNO2 Nitrite
HNO3Nitrate
H2SO4 Sufate
H3PO4Phosphate
H2SO3Sulfite
H2CO3Carbonate
Nitrous Acid
Nitric Acid
Sulfuric Acid
Phosphoric Acid
Sulfurous Acid
Carbonic Acid
Name common binary acids and oxyacids given their chemical formulas
What is a base?
A base is a solution that has an excess of OH- ions.
Chemists sometimes use the term “alkali” for a base that is soluble in water.
Alkali is of Arabic origin meaning “ashes of a plant.”
Bases are substances that can accept hydrogen ions, H+ (proton acceptors)
Define acid and base according to Bronsted-Lowry theory
Properties of Bases
Feel Slippery Taste Bitter Corrosive Can conduct electricity. (Think
alkaline batteries.) Do not react with metals. Turns red litmus paper blue. pH above 7
List the general characteristics of acids and bases.
Some Common Uses of Bases Bases give soaps, ammonia, and many
other cleaning products some of their useful properties.
The OH- ions interact strongly with certain substances, such as dirt and grease.
Chalk and oven cleaner are examples of familiar products that contain bases.
Your blood is a basic solution. Quinine is base used as a drug to treat
malaria. Lidocaine, a local anesthetic used by
dentists, is a base. Like acids, some bases are harmless
while others are very dangerous.
Solutions Most acids and bases
dissolve in water. A solution is a
homogenous mixture of 2 or more substances
The solute is the substance(s) present in the smaller amount(s)
The solvent is the substance present in the larger amount
Define the terms solute, solvent, solution, solubility and molarity
Solutions How well a solute dissolves in a solvent is called
solubility. We used the solubility table to determine if a
precipitate formed in a chemical reaction. Acids and bases are soluble in water The properties of acids and bases are only
exhibited when they are in solution Many factors affect solubility such as pressure,
amount of solute, amount of solvent, and temperature. (think about making Kool-Aid)
Define the terms solute, solvent, solution, solubility and molarity
Molarity Molarity (M) is a measure of
the concentration of a solution.
Concentration – how much solute in comparison to how much solvent
Define the terms solute, solvent, solution, solubility and molarity
CALCULATING MOLARITY1. Calculate moles of solute2. Convert units of solution to liters3. Use molarity formula
Calculate molarity
CALCULATING MOLARITY1. Calculate moles of solute2. Convert units of solution to
liters3. Use molarity formula
12.6 g of NaCl are dissolved in water making 344mL of solution. Calculate the molar concentration.
12.6 g NaCl 58.443 g NaCl 1 mol NaCl
= 0.216 mol NaCl
344 mL sol’n
1000 mL
1 L= 0.344 L sol’n
𝑴=𝒎𝒐𝒍𝑳 ¿
𝟎 .𝟐𝟏𝟔𝒎𝒐𝒍𝟎 .𝟑𝟒𝟒 𝑳 ¿𝟎 .𝟔𝟐𝟖𝑴
Calculate molarity
CALCULATING MOLARITY1. Calculate moles of solute2. Convert units of solution to
liters3. Use molarity formula
46.8 g NaHCO3
84.006 g NaHCO3
1 mol NaHCO3 = 0.557 mol NaHCO3
350 mL sol’n
1000 mL
1 L= 0.35 L sol’n
𝑴=𝒎𝒐𝒍𝑳 ¿
𝟎 .𝟓𝟓𝟕𝒎𝒐𝒍𝟎 .𝟑𝟓𝑳 ¿𝟏 .𝟔𝑴
What is the molarity of 350 mL of a solution containing 46.8 g of NaHCO3?
Calculate molarity
CALCULATING MOLARITY1. Calculate moles of solute2. Convert units of solution to
liters3. Use molarity formula
0.313 mol LiOH 23.948 g LiOH
1 mol LiOH = 7.50 g LiOH
250.0 mL sol’n
1000 mL
1 L= 0.2500 L sol’n
𝑴=𝒎𝒐𝒍𝑳
𝟏 .𝟐𝟓=𝒙𝒎𝒐𝒍
𝟎 .𝟐𝟓𝟎𝟎𝑳𝒙=𝟎 .𝟑𝟏𝟑𝒎𝒐𝒍
How many grams of LiOH is needed to prepare 250.0 mL of a 1.25 M solution?
Calculate molarity
CALCULATING MOLARITY1. Calculate moles of solute2. Convert units of solution to
liters3. Use molarity formula
0.35 L 1000 mL
1 L= 350 mL solution
25 g H3PO4
97.994 g H3PO4
1 mol H3PO4 = 0.26 mol H3PO4
𝑴=𝒎𝒐𝒍𝑳 𝟎 .𝟕𝟓𝐌=
𝟎 .𝟐𝟔𝒎𝒐𝒍𝒙 𝑳
𝒙=𝟎 .𝟑𝟓𝑳
What volume of solution will contain 25 g of H3PO4 if the solution concentration is 0.75 M?
Calculate molarity