C2.1 Electricity and Chemistry Flashcards
electrolysis means
The breaking down (decomposition) of an ionic compound by the use of electricity.
positive electrode is…….
Anode
What two conditions must exist for a substance to be an electrolyte and allow an electric current to pass through it.
The substance must contain IONS and they must FREE to MOVE (in molten/liquid state or dissolved in water)
an inert electrode is……..
An inert electrode is an NONREACTIVE electrode.
it will not be changed during electrolysis.
Give an example of a substance that is often used as an inert electrode
Carbon
Platinum
What products formed when lead (ll) chloride are electrolysed
lead and carbon
What products formed when magnesium oxide are electrolysed
magnesium and oxygen
What products formed when aluminium oxide are electrolysed
aluminium and oxygen
What is an exothermic reaction
A reaction that releases heat energy to the surroundings
What is endothermic reaction
A reaction that absorbs energy from the surroundings
why do polystyrene cups make good calorimeters for measuring energy changes in some chemical reactions
Polystyrene is a very good insulator and so very little energy is transferred to the surroundings.
negative electrode is…….
cathode
