Chemistry Unit 4

Metal reaction with water

Metal Hydroxide + Hydrogen

Metal reaction with oxygen

Metal oxide

Metal reaction with acid

Salt + hydrogen

Salts

salt:

Nitric acid= nitrate

Sulfuric acid= sulfate 

Hydrochloric acid= chloride 

Phytomining + pros & cons

Phytomining uses plants to extract copper from soils containing low grade copper ore.

Advantages: uses low grade ores, reduces open cast mining, photosynthesis uptakes CO2. Disadvantages: Relatively energy intensive.

Reactivity Series of Metals

Potassium, Sodium, Lithium, Calcium, Magnesium, Aluminium, Carbon, Zinc, Iron, Lead, Hydrogen, Copper, Silver, Gold

Cations & Anions

Cations: positively charged ions 

Anions: negatively charged ions

Displacement reaction

Displacement reaction: when a more reactive metal will displace a less reactive metal to form a compound

Metal ore

• Most metals are found as metal ores

• A metal ore is a rock that contains enough metal to be economically viable to extract

• Most ores are metal oxides (bonded with oxygen)

No need for extraction

• Silver, gold, and platinum are unreactive so they are found in their native state

How to extract the metal from ore

Too extract the metal from the ore, oxygen has to be removed this is known as reduction

Metals below carbon are extracted by heating with carbon 

Metals more reactive than carbon are extracted using electrolysis 

Reduction & Oxidation

• Oxidation is loss of electrons, gain of oxygen. Reduction is gain of electrons, loss of oxygen 

Advantages of Recycling Metals

Takes less energy

Conserves finite resources

Cuts down on waste

Lowers financial cost

Less impact on the environment

Disadvantages of Recycling Metals

They have to be sorted and separated (cost time and money)

Energy is needed to collect, transport, and recycle the metals (less than extraction tho)

Bioleaching

Bioleaching uses bacteria to extract copper from low grade ore. 

Advantages: Highly efficient, less energy intensive, cost-effective. Disadvantages: very slow, may contain toxic waste.