redox 1 p1,2

Question 1

what is an oxidation number?

Answer 1

number of elctrons an atom uses to bond with any other atom

Question 2

what is the oxidation number of an uncombined element such as C, H, ect?

Answer 2

0

Question 3

what is the oxidation number of oxygen such as in H2O?

Answer 3

-2

Question 4

what is the oxidation number of oxygen in peroxides?

Answer 4

-1

Question 5

what is the oxidation number of combined hydrogen?

Answer 5

+1

Question 6

what is the oxidation number of combined hydrogen in metal hydrides such as LiH?

Answer 6

-1

Question 7

what is the oxidation number of a simple ion?

Answer 7

charge on the ion
e.g. Na+ –> +1

Question 8

what is the oxidation number of combined F?

Answer 8

-1

Question 9

when an element has more than one stable oxidation number how is it indicated?

Answer 9

roman numeral
e.g. iron (II)

Question 10

what are oxyanions?

Answer 10

negative ions that have an element along with oxygen

Question 11

define oxidation in terms of electron transfer and oxidation number

Answer 11

oxidation is
loss of electrons
increase in oxidation number

Question 12

define reduction in terms of electron transfer and oxidation number

Answer 12

gain of electrons
decrease in oxidation number

Question 13

what is a redox reaction?

Answer 13

a reaction in which both oxidation and reduction takes place

Question 14

what is an oxidising agent?

Answer 14

species that gains electrons

Question 15

what is a reducing agent?

Answer 15

species that lose electrons

Question 16

oxidation state of Cl in NaClO?

Answer 16

+1
normally -1

Question 17

disproportionation

Answer 17

where in a redox reaction, the oxidation states of atoms of the same element, increase for some atoms, whereas decrease for some atoms

element is oxidised and reduced

Question 18

why is 2CrO4 2- + 2H+ –> Cr2O7 2- + H2O not a redox reaction?

Answer 18

chromium is oxidised but hydrogen remains the same oxidation state