Redox Flashcards
What is the oxidation number of an element a measure of?
The number of electrons that an atom uses to bind
The sum of all oxidation number in a neutral compound is…
0
Sum of all oxidation number in a neutral compound = 0 examples
NaCl and Caco3
The sum of all oxidation numbers in an ion is equal to the…
Charge
Sum of all oxidation number in an ion = overall charge examples
SO4 2- so oxidation numbers sum to 2-
The oxidation’s number is any uncombined element is…
0
Uncombined elementary examples
Diatomics and single metals
The oxidation number of oxygen in any compound is…
-2
Exception of oxygen being -2 is…
Peroxides e.g. H2O2 where it’s -1
The oxidation number of hydrogen in any compound is..l
+1
Exception of hydrogen being +1 in a compound
Hydrides e.g. LiH where it’s -1
In a compound, a group 1 element always has an oxidation number of…
+1
In a compound, a group 2 element always has an oxidation number of…
+2
In a compound, a group 3 element always has an oxidation number of…
+3
What is different about group 7?
Can have different oxidation numbers
Group 7 exception
Fluorine
What does it mean for the more electronegative element in the compound’s oxidation number?
A more negative oxidation number
Exceptions
Metal hydrides = -1
Hydrogen peroxide = -1
Oxygen diflouride = +2
Oxidation number +/- location
Before the number
Charge +/- location
After the number
How are elements that can have more than one oxidation state?
As a Roman numeral (systematic name) - typical for transition elements
What are oxyanions?
Negative ions containing oxygen and 1 or more element
Oxyanions usually end in?
-ate
Examples of oxyanions
NO2 -, NO3 -, SO3 2-, SO4 2-
