REDOX

Question 1

name 4 acids

Answer 1

HCl hydrochloric acid
HNO3 nitric acid
H2SO4 sulfuric acid
CH3COOH ethanoic acid

Question 2

what do all acids contain

Answer 2

Hydrogen

Question 3

what happens when u dissolve acid in water

Answer 3

hydrogen released as H+ (a proton)
so the acid dissociates (splits) to form a positive and negative ion

Question 4

strong acids definition

Answer 4

complete dissociate in aqueous solutions, fully releasing H+ ions

Question 5

strong acid examples

Answer 5

HCL
H2SO4
HNO3

Question 6

weak acid definition

Answer 6

only partially dissociates in aqueous solutions, so only small number of molecules releases H+ ions

Question 7

example of weak acid

Answer 7

CH3COOH

Question 8

base definition

Answer 8

substance that can neutralise acid to form a salt and water
H+ (proton) acceptors

Question 9

alkali definition

Answer 9

a base that is soluble in water

Question 10

base examples

Answer 10

CuO copper oxide (any metal oxide)
Mg(OH)2 magnesium hydroxide (and metal hydroxide)
NH3 ammonia
Na2CO3 (metal carbonate)

Question 11

base + acid

Answer 11

-> salt + water

Question 12

carbonate + acid

Answer 12

-> salt + water + CO2

Question 13

ammonia + acid

Answer 13

-> ammonium salt

Question 14

oxidation

Answer 14

loss of electrons

Question 15

reduction

Answer 15

gain of electrons

Question 16

oil rig

Answer 16

oxidation is loss
electron is gain

Question 17

redox reaction

Answer 17

when reduction and oxidation of electrons simultaneously occur in one reaction

Question 18

oxidation number

Answer 18

is the oxidation state for elements or ionic substances

Question 19

oxidation of an element is

Answer 19

0

Question 20

oxidation of a neutral compounds

Answer 20

sums to 0

Question 21

oxidation of a charged compound

Answer 21

sums to the overall charge

Question 22

oxidation state of H in compound

Answer 22

+1

Question 23

oxidation state of O in compound

Answer 23

-2

Question 24

oxidation state of halogens (gp7) in compounds

Answer 24

-1

Question 25

oxidation states of alkali metals (gp1) in compounds

Answer 25

+1

Question 26

oxidising agent

Answer 26

electron acceptor (gets reduced)

Question 27

reducing agent

Answer 27

electron donator (gets oxidised)

Question 28

an increase in oxidation number means

Answer 28

electrons lost so oxidised and therefore is a reducing agent

Question 29

a decrease in oxidation number means

Answer 29

electrons gained so reduced and therefore it is an oxidising agent

Question 30

half equation shows

Answer 30

seperates reduction and oxidation equations that happen in a redox reaction

Question 31

how to write half eq

Answer 31

balance species balance oxygens by adding H2O balance Hydrogens by adding H+ balance electrons by adding e-

Question 32

oxidation state of oxygen in peroxides (e.g has O2)

Answer 32

-1

Question 33

What is a disproportionation reaction?

Answer 33

a specie that is simultaneously both reduced and oxidised

Question 34

best reducing agents

Answer 34

alkali metals as they have low ionisation energies (so donates outer electron easy) atomic radius increases down group so donates electrons easier

Question 35

test for oxidising agent

Answer 35

turns potassium iodide from colourless to brown

Question 36

test for reducing agent

Answer 36

turns acidified potassium manganate from purple to colourless