Need to remeber Flashcards
What is a aldehyde functional group?
Carbonyl group and H group + R group
What is a ketone functional group?
Carbonyl group and two R groups
What is a Ether?
Oxygen bonded to two R groups
What is an ester?
Carbonyl group bonded to OR group and R group
Why is water a good solvent and what does this allow it do do?
Water is a good solvent as it is a polar molecule, which allows it to engage in hydrogen bonding with itself and other molecules
What are some unusual properties of water?
- -> High melting point and boiling point
- -> Solid water is less dense then liquid water
How does water interact with ionic substances
–> Hydrogen atoms on the water molecule stabilise the negative charge of the anion
–> Oxygen atom stablises the cation
These stabilising attractive interactions overcome the energy required to separate the cations and anions in the solid
What is a dipole-dipole interaction?
When a polar molecule dissolves in water a dipole dipole interaction between the temporary charges on the polar molecule and water molecule drives the dissolution
What happens in equalibrium if K is large?
The equ position has more products then reactants (the position of equ lies to the right)
What happens in equ if K is small?
If K is small, the equ has more reactants then products (It lies to the left)
When is K constant?
At a constant temperature
What is Q?
The reaction quotent describes the composition at any point in the equ
–> Q can have any positive value, before the reaction, it is 0. Once it starts the value of Q increases until Q = K
Where will the equ lie if Q > K?
Position of equ will move towards the left
Where will the equ like if Q < K?
The position of equ will move to the right
Do catalysts affect the position of equ?
No they only increase the rate at which a system reaches equ
When will a solvent dissolve until?
Until the maximum value is s is reached. The equ is said to be saturated, and the equalibrium solute to solute exists.
What does how much a compound will dissolve depend on?
- -> Chemical nature
- -> Temperature
- -> Pressure if gas
When will a precipitate form?
When Qsp > Ksp
What is the common ion effect?
If a sparing soluble salt is dissolved in a solution that already contains either the cation or the anion in a solt, the solubility of the salt will be reduced (Ksp does not chang)
What is the solubility equation?
Ksp = s x s (s^2)
What are lewis acids and bases?
A lewis acid is an electron pair acceptor, A lewis base is a electron pair donor
What are bronsted lowry acids and bases?
A acid is a proton donor
A Base is a proton acceptor
What is Kw?
The equalibrium constant for the process of autoionisation (water can act as both a acid and base)
In neutral water H3O+ = OH- (1x10^7 mol L-1)
What does a large value of Kb/ Ka mean?
The the level of dissociation is greater –> so it is a better acid/ base
What are the two assumptions when calculating a weak acid/ weak base’s pH?
- [H3O+]e = [Conjugate base]e
2. [Weak acid]e = [Weak acid]i
