Chemical Changes Flashcards
Oxidised meaning
(Both in terms of O2 and electrons)
Gains oxygen
Loses electrons
Reduction reaction
(Both in terms of O2 and electrons)
Oxygen is lost
Electrons are gained
How would you make a reactivity series?
React the metals with water.
Potassium - very vigorous
Sodium - very reactive
Lithium - still reactive, less than sodium
Etc, etc
The less reactive metals would be reacted with dilute acids.
Zinc
Iron
Hydrogen
Copper
Reactivity series
(The metals in order, as well as hydrogen and carbon)
Potassium
Sodium
Lithium
Calcium
Magnesium
Carbon
Zinc
Iron
Hydrogen
Copper
The reaction of elements are based off of what?
Their ability to lose or gain electrons
More reactive, more likely to form ions.
Why can gold be found in the Earth as an ore?
It is so inert, it doesn’t react with oxygen (and other elements).
What is an ore?
A naturally occurring rock, which has sufficient metal, or metal compounds, to be extracted.
What is the extraction of a metal?
What reaction does it involve?
A more reactive metal replaces a less reactive metal from its compound.
A displacement reaction.
An example of a half equation for oxidation.
(Use Mg)
Mg -> Mg2+ + 2e-
Oxidation because it loses electrons.
An example of a half equation for reduction.
(Use Cu)
Cu2+ + 2e- -> Cu
What kind of reaction is the following:
Zinc + copper sulfate -> zinc sulfate + copper
Displacement reaction
Acids must be an aqueous solution to produce H+ ions.
True or false?
True
Must be dissolved in water.
What is a base?
Examples?
Chemicals that can neutralise acids
Metal oxides or metal hydroxides
Bases + Acids -> …
Salt + Water
What is an alkali?
Soluble bases
Produce OH-
