Chapter 3 Flashcards
What do oxidation numbers tell you about?
How many electrons an atom has donated or accepted to form an ion
What is the oxidation number of all uncombined elements?
0
What is the oxidation number of all elements that are bonded to identical elements?
0
What is the oxidation number of hydrogen in H2?
0
What is the oxidation number of a simple, monatomic ion?
The same as its charge
For molecular ions, what is the sum of the oxidation numbers equal to#?
The overall charge of the ion
For a neutral compound, what is the overall charge?
0
So, for a neutral compound what is the sum of the oxidation numbers?
0
When is the only time that hydrogen doesn’t have an oxidation number of +1?
In metal hydrides
When is the only occasion that oxygen doesn’t have an oxidation number of -2?
In peroxides (O2)2-
What do roman numerals tell you?
The oxidation number of the elements
In copper(I) oxide, what is the oxidation number of copper?
+1
What is the formula of copper (I) oxide?
Cu2O
What do ions ending in ‘ate’ contain?
Oxygen and another elements
What is the formula of a nitrate ion?
NO3-
What is the oxidation number of H in H2?
0
What is the usual oxidation number of oxygen when its combined with another elements?
-2
What is a redox reaction?
When electrons are transferred in a reaction
What is oxidation?
A loss of electrons
What is reduction
A gain in electrons
What is an oxidising agent?
An element that accepts electrons and gets reduced
What is a reducing agent?
An element that donates electrons and gets oxidised
What is a disproportionation reaction?
A special redox reaction, where an element in a single species is simultaneously oxidised and reduced
What can ionic half equations show?
Oxidation and reduction
What can you combine half-equations for different oxidising or reducing agents together to make?
Full equations for redox reactions
In order to balance ionic half equations, what 3 elements/compounds can you use to balance the equation?
e-, H+ and H20
