2 Acids Sour tastes pH: 0 – 6.9 Reacts with carbonate to produce CO2 gas.Turns Litmus fromBlue to Red.Reacts with metals toproduce hydrogen gas.
3 Acids Acids Solutions conduct electricity (In ion form) Strong (99%) HCl (aq) + H2O (l) H+ (aq) Cl- (aq)orH2SO4 (aq) + H2O (l) H+ (aq) + HSO4- (aq)Weak or strong acids depends on how much the acid dissociates.
4 Bases Bitter Taste pH: 7.1 – 14 Turns Litmus from Red to Blue Reacts with acids toform salts.Slippery feel
5 Bases Weak or Strong depends on how much it dissociates. Weak (4%) Na2CO3 (aq) + H2O (l) Na+ (aq) + CO3- (aq)Strong (99%)NaOH (aq) + H20 (l) Na+ (aq) + OH- (aq)
6 What is an Acid and What is a Base? Define acid and base in terms of water.H2O or HOHH-OH <Molecular StructureH+ = Hydrogen (Acid)OH- = Hydroxide (Base)If you have more hydrogen then hydroxide, you have an acid
7 What is an Acid and What is a Base? If you have more hydroxide then hydrogen you have a base.H+ = AcidOH- = BaseHOH (H2O) = NeutralWe measure acid and Base on the “pH” scale.
13 Types of AcidsMonoprotic acids contain only one acidic hydrogen.
14 Types of Acids Diprotic contains 2 acidic hydrogens Triprotic contains 3 acidic hydrogensPolyprotic- more than 1 acidic hydrogen
15 Types of AcidMost acids are oxyacids, where the acidic proton is attached to an oxygen atom.HNO3 Nitric AcidH2SO4 Sulfuric AcidH3PO4 Phosphoric Acid
16 Types of Acids Amphoteric- can act as an acid or a base. H2O H2O H3O OH-Acid (1) Base (1) Acid (2) Base (2)The above is an autoionization of H2O, and involves the transfer of a proton from one water molecule to another to produce a OH- and H3O+.
17 Buffers and Buffer Solutions A buffered solution is one that “resists a change is its pH”, when either a hydroxide, OH- or hydrogen, H+, are added.Blood is a good example of a buffer.A buffer contains 2-components: an acid to neutralize the addition of OH-, and a base to neutralize the H+ from the addition of an acid.
18 Buffers and Buffer Solutions When base (OH-) is added to a buffer solution, the acid in the buffer provides H+ ions, which neutralizes the base, thus, preventing a large change in pH.
19 Buffers and Buffer Solutions The blood’s primary buffer system is made up of carbonic acid (H2CO3) and sodium bicarbonate(NaHCO3).H HCO H2CO3From Acid In Buffer Carbonic AcidOH H2CO HCO H2OFrom Base In Buffer Bicarbonate IonBuffer is weak base ammonia and its salt, used equation on page 531 to explain the buffer system.
20 Buffers and Buffer Solutions Original BufferpHAdded OH- ion replacedby acid ionorAdded H+ ion replacedby base ionFinal pH of BufferClose to original
21 Acids and BasesBases are ionic compounds containing metal cations and the hydroxide ion, OH-.When a “Base” completely dissociates in water to produce OH-, it is referred to as Alkaline.
22 Bronsted-Lowery Acids and Bases Bronsted–Lowery Acid is a molecule or ion that is a proton (H+) donor.Bronsted-Lowery Base is a molecule or ion that is a proton (H+) acceptor.
23 Bronsted-LoweryBronsted-Lowery Acid is a molecule that is a Proton Donor.ExampleHCl NH NH Cl-The proton is transferred from the hydrogen chloride to ammonia.
24 Bronsted-LoweryBronsted-Lowery Base is a molecule that is a proton acceptor.ExampleHCl NH NH Cl-Proton ProtonDonor AcceptorAcid Base
25 Dissociates / IonizesA strong acid is one that ionizes completely in an aqueous solution.A strong acid is a strong electrolyte.Electrolyte – Any compound that conducts electricity when melted or dissolved in water.
26 Dissociates / IonizesAcids that are weak electrolytes are known as weak acids.They do not dissociate or ionize very much.Dissociation- The separation of ions that occurs when an ionic compound dissolves.Ionization-The process where ions form from a covalent compound.
28 Arrhenius Acids and Bases An Arrhenius Acid is a chemical compound that increases the concentration of hydrogen ions, H+, in an aqueous solution.Arrhenius Base is a substance that increases the concentration of hydroxide ions, OH-, in an aqueous solution.
29 Conjugated Acid and Bases When an acid gives up a proton, it can re-accept the proton and acts as a base.HF H2O F H3O+Acid Base Conjugated ConjugatedBase AcidIn the above reaction the water molecule is a Bronsted-Lowery Base. The hydronium ion is now able to donate a hydrogen proton, so it is called a conjugated acid.
30 Lewis Acids and Bases A Lewis acid is an electron-pair acceptor. A Lewis base is an electron-pair donor.H [ O – H ] H OHLewis Acid Lewis Base
32 Neutralization Reaction The reaction of an acid and base is called a neutralization reaction because the properties of both the acid and base are diminished of neutralized when they react.
33 Concentration of Solution The concentration of a solution is a measure of the amount of the solute (solid) in a given amount of solvent (Liquid).Molarity- The number of moles of a solute in one liter of solution.Molarity, M= Moles/Liter
34 Concentration of Solution If 3 moles of LiCl are added to 100 L of water, what is the molarity of the solution?3 mol/100 L = 0.03 M of LiCl
35 Concentration of Solution If you put 20.0 g of NaOH in 1-liter of water, what is the molarity (M).20.0g NaOH mole = 0.5 mole40.0 g NaOH0.5 mol/1.0 L = 0.5 M of NaOH
36 Concentration of Solution If you put 50.0 g of HCl in 2.0 liters of water, what is the molarity (M)?50.0g HCl mole = 1.37 mole36.46 g HCl1.37 mol/2.0 L = 0.69 M of HCl
37 Concentration of Solution When making-up a solution:M1V1=M2V2M1 = Initial or Beginning MolarityV1 = Initial or Beginning VolumeM2 = Final or Ending MolarityV2 = Final or Ending Volume
38 Concentration of Solution If you have 300mL of a 0.5 M solution of HNO3. What volume of water needs to be added to get 0.8 M solution of HNO3?M1 = 0.5 MV1 = 300 mLM2 = 0.8 MV2 = ?M1V1=M2V2
39 If you have 56 mL of a 3 M solution of H2SO4 If you have 56 mL of a 3 M solution of H2SO4. What volume of water needs to be added to get 0.1 M solution of H2SO4?M1 = 3 MV1 = 56 mLM2 = 0.1 MV2 = ?
40 If you have 56 mL of a 3 M solution of H2SO4 If you have 56 mL of a 3 M solution of H2SO4. What will the concentration of H2SO4 be if we add 1000mL (1L) of water?M1 = 3 MV1 = 56 mLM2 = ? MV2 = 1000 mL
41 If you have 5 mL of a 12 M solution of HCl If you have 5 mL of a 12 M solution of HCl. What will the concentration of HCl be if we add 500mL (1L) of water?M1 = 12 MV1 = 5 mLM2 = ? MV2 = 500 mL
42 Acid-Base TitrationThe general process of determining the molarity of an acid or a base through the use of an acid-base reaction is called an acid-base titration.
43 Acid-Base TitrationThe known reactant molarity is used to find the unknown molarity of the other solution.Solutions of known molarity that are used in this fashion are called standard solutions.In a titration, the molarity of one of the reactants, acid or base, is known, but the other is unknown.