Unit 3-Metals Flashcards
Every metal conducts electricity. Explain.
In metallic bonding, the outer electrons are delocalised (free to move). This means an electrical current can flow through metallic materials.
What is the word equation for when metals react with water?
metal + water → metal hydroxide + hydrogen
What are the word, balanced chemical and ionic equations when magnesium reacts with water?
magnesium + water → magnesium hydroxide + hydrogen
Mg + 2H2O → Mg(OH)2 + H2
Mg(s) + 2H2O → Mg2+(aq) + 2OH-(aq) + H2(g)
What is the word equation for when metals react with oxygen?
metal + oxygen → metal oxide
What are the word, balanced chemical and ionic equations when zinc (II) oxide is formed?
zinc+ oxygen → zinc (II) oxide
2Zn+ O2 → 2ZnO
2Zn(s) + O2(g) → 2Zn2+O2-(s)
What is the word equation for when metals react with acid?
metal + acid→ metal salt + hydrogen
What are the word equation, balanced formula and ionic equations for lithium reacting with hydrochloric acid?
lithium + hydrochloric acid → lithium chloride + hydrogen
2Li + 2HCl → 2LiCl + H2
2Li(s) + 2H+(aq) + 2Cl<span>-</span>(aq) → 2Li+(aq) + 2Cl<span>-</span>(aq) + H2(g)
Without spectator ions
2Li(s) + 2H+(aq) → 2Li+(aq) + H2(g)
Describe how the following metals can be extracted from their ores.
- Silver, Gold and Mercury
- Copper, Lead and Iron
- Aluminium, sodium and potassium
- Unreactive metals can be extracted by heat alone.
- Metals in the middle of the electrochemical series can be extracted by heating with carbon or carbon monoxide.
- Reactive metals must undergo electrolysis (using a direct current (DC supply) to be extracted.
Describe how an electrochemical cell is set up.
A simple cell can be made by placing two metals in an electrolyte and connecting using wires.
What is meant by a half cell?
Metals in solutions of their own ions. (Copper in copper sulphate)
What name is given to the device used to link half cells and completes the circuit?
Ion bridge (salt bridge)
Different pairs of metals produce different voltages.
How can we predict the size of voltage?
The further apart elements are in the electrochemical series, the greater the voltage produced.
Do electrons flow from the higher metal in the ECS (electrochemical series) to the lower or lower to highest?
Higher to lower.
What word is used to describe the reaction where a metal has lost electrons?
Oxidation is loss.
What word is used to describe the reaction where a metal has gained electrons?
Reduction is gain of electrons.