07 - redox reactions

Question 1

oxidation

Answer 1

loss of electrons from an atom, ion or molecule

Question 2

reduction

Answer 2

gain of electrons by an atom, ion or molecule

Question 3

OILRIG

Answer 3

Oxidation Is Loss
Reduction Is Gain

Question 4

redox reaction

Answer 4

a reaction in which oxidation and reduction take place at the same time

Question 5

half equations

Answer 5

an equation whcih shows either oxidation or reduction only

Question 6

oxidation number

Answer 6

a number given to each atom/ion in a compound that shows us its degree of oxidation

Question 7

oxidation number rule

Answer 7

. number of any uncombined element = 0
. group 1= +1
. group 2 = +2
. flourine = -1
. hydrogen = +1
. oxygen = -2 (expect peroxides, -1, and F2O, +2)
. sum of oxidation numbers in a compound = 0
. more electronegative atoms is given the negative oxidation number

Question 8

oxidising agent

Answer 8

a substance that brings about oxidation by removing electrons from another atom/ion

Question 9

reducing agent

Answer 9

a substance that brings about reduction by donating electrons to another atom/ion

Question 10

numbers in roman numerals after the name of atom in a compound is

Answer 10

showing oxidation number

Question 11

balancing chemical equations using oxidation numbers

Answer 11

balanced increase in ox. no. and decrease in ox.

Question 12

disproportionation reaction

Answer 12

the simultaneous oxidation and reduction of the same species in a chemical reaction

Question 13

Cl2 + 2NaOH (cold)

Answer 13

NaCl + NaClO + H2O