Electrolysis + Energetics & Acids/Alkalis Flashcards
What’s Electrolysis?
Splitting up substances (made up of ions) using electricity.
How does electrolysis work? (Simple)
An electric current is used to separate ions in a substance.
What’s the name for the substance that’s being broken down?
Electrolyte
What’s an electrode?
Conductor of electricity that carries current into electrolyte splitting it.
What’s the Anode?
Positive charged Electrode
What’s the cathode?
Negatively Charged Electrode
What’s the cation?
Positive charged ion
What’s the anion?
Negatively charged ion
Which ions are attracted to Anode?
Negatively Charged Ions (Anions)
Which ions are attracted to Cathode?
Positively charged Ions (Cations)
What happens at the anode?
Negative ions lose electrons to become atoms/molecules.
What happens at the cathode?
Positive Ions gain electrons to become atoms/molecules.
Reduction or Oxidations? CATHODE
Reduction
Reduction or Oxidation? ANODE
Oxidation
What do water molecules break up in electrolysis?
H+ & OH- ions.
What are the rules for anode (electrolysis)?
- If - ions are halides (Cl, Br…) then the halogen is produced.
- If - ions aren’t halides (CO3, NO3…) then oxygen is produced.
What are the rules for cathode? (electrolysis)
- If + ions (metals) are more reactive than Hydrogen, then Hydrogen is produced.
- If + ions (metals) are less reactive than Hydrogen, then that metals is produced?
Which metals are less reactive than Hydrogen?
Copper, Silver & Gold.
What’s an acid?
Contain Hydrogen, and release Hydrogen ions when dissolved in water.
What’re bases?
- Opposite to acids
- Contain elements that react with acids to make water
What’s an alkali?
- Are bases
- Contain OH- ions
Word equation for neutralisation?
Acid + Alkali —> Salt + Water
Acid & Carbonate reactions?
Acid + Carbonate —> Salt + water + carbon dioxide
Metal & Acid reactions?
Acid + Metal —> Salt + Hydrogen
What does a catalyst do?
- Lowers activation energy
So: - Bonds break more easily
- Reaction is faster
What releases energy? (energetics)
Forming new bonds
What takes in energy? (energetics)
Breaking bonds
