give 3 examples of REDOX reacions
- ionic bonding
- displacement reactions
- electrolysis
What is oxidation?
- the addition of [O]
- the loss of [H]
- the loss of electrons
Oxidation Is Loss (of electrons)
What is reduction?
- the loss of [O]
- the gain of [H]
- the gain of electrons
Reduction Is Gain (of electrons)
What is an oxidising agent?
a species that facilitates oxidisation by accepting electrons which need to be lost. It itself is reduced. [O] is electron deficient
What is a reducing agent?
a species that facilitates reduction by donating electrons which need to be gained. It itself is oxidised
What will you observe when a piece of magnesium metal is added to a solution of copper sulphate? And what type of reaction is it?
- A pink-brown ppt is formed which is Cu
- Mg dissolves
- Blue solution would decolourise
displacement reaction
Describe what a mechanism is for redox equations
shows how the electrons move via half equations
What is a half equation?
an equation that shows loss or gain of electrons
What are the 3 rules of going about half equations?
- balance the atoms using H2O and H+ ions
- balance the equation using mole numbers
- balance the charge using electrons
How do you get the overall reaction for a redox reaction?
do the 2 mechanisms (O: and R:) and add then together cancelling out the electrons. You may have to multiply the equations to get the same amount of electrons on both mechanisms
When might a reaction not be a REDOX reaction?
when there is no change in oxidation state
How can the reducing ability of the halides be tested experimentally?
by the reaction of solid halides with conc H2SO4
If a halide is capable of reducing conc sulphuric acid (H2SO4), what happens?
1, halide is oxidised to halogen
2. H2SO4 is reduced
