redox

Question 1

reactions that are not redox

Answer 1

-neutralisation reactions of acids and bases
-precipitation reactions

Question 2

disproportionation reactions

Answer 2

-redox reaction where a substance is both oxidised and reduced

Question 3

definitions of redox

Answer 3

oxidation
-gains oxygen
-loses hydrogen
-loses electrons
-increase oxidation state

reduction
-loses oxygen
-gains hydrogen
-gains electrons
-decrease oxidation state

Question 4

rules of oxidation state

Answer 4

-elemental state always 0
-monatomic ion is its charge
-fluorine always -1
-oxygen usually -2 except OF2 or H2O2
-hydrogen usually +1 except metal hydrides NaH
-sum of o.s in neutral compound = 0
-sum of o.s in polyatomic ion = overall charge

Question 5

oxidising agent

Answer 5

-oxidises another substance but is reduced

test for reducing agent
-acidified KMnO4, turns purple to colourless
-acidified K2Cr2O7, turns orange to green

Question 6

reducing agent

Answer 6

-reduces another substance but is oxidised

test for oxidising agent
-potassium iodide, turns colourless to brown