CHEM105 Chapter Notes -Conjugate Acid, Weak Base, Rate Equation
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Chapter 16, Kinetics
16.2 Expressing the Reaction Rate
If we have the chemical reaction,
Then the reaction rate in terms of concentration can be expressed as:
16.3 The Rate Law and its Components
The rate law has the form:
Where A and B are concentrations, k is the rate constant and is specific for the given
reaction and changes with temperature. m and n are the reaction orders, if m or n are zero,
then the rate doesn’t depend on that chemical. The components of the rate law MUST be
found by experiment, it isn’t possible to use reaction stoicheometry.
Reaction order technology:
Chapter 18, Acid-Base Equilibria
The meaning of Ka:
This specific equilibrium constant highlights only the species whose concentrations change
to any significant extent. It follows the general products over reactants rule. Like the other
equilibrium constants, it is temperature dependant.
Classifying the Relative Strengths of acids and bases:
Strong Acids: there are two types that should be memorized
1. The hydrohalic acids, HCl, HBr, HI
2. Oxoacids in which the number of O atoms exceeds the number of ionisable
protons by two or more, such as HNO3 , H2SO4 and HClO4
Weak acids: there are four types of weak acids
1. The hydrohalic acid, HF
2. Acids where the H isn’t bonded to an oxygen or a halogen, HCN and H2S
3. Oxoacids where the number of O atoms equals or exceeds by one the number of
ionizable protons, HClO, HNO2, H3PO4
4. Carboxylic acids (general formula=RCOOH) such as CH3COOH
Strong Bases: which are water soluble compounds containing O2- or OH-.
1. These are either group one or group two metals which are bonded to either of
those two ions.
*MgO and Mg(OH)2 are only slightly soluble in water, but the soluble portion
Weak bases: Many compounds with an electron rich nitrogen atom are weak bases. A
common structural feature is that the nitrogen atom has a lone pair.
18.2 Autoionization of Water and the pH scale
Autoionization is a trait given to pure water because it will (very slightly) dissociate into its
ions on its own.
18.3 The Bronsted and Lowry Definition:
The definition is that an acid is a proton donor and a base is a proton receiver.
From the Bronsted and Lowry perspective, the only requirements is that one species
donates, and the other receives.
Relative Acid-Base Strength and the Net Direction of Reaction: