Reactions of Metals and Group 1 Alkali Metals

• Magnesium reacts with oxygen to produce magnesium oxide, which appears as a white solid
• Magnesium reacts with hydrochloric acid to produce magnesium chloride and hydrogen
• This reaction results in effervescence, heat, and the dissolving of magnesium
• Copper sulphate reacts with magnesium to produce magnesium sulphate and copper
• This reaction results in a black solid forming and the solution turns paler blue

Group 1: Alkali Metals

• Group 1 metals are the most reactive metals
• Reactivity increases down the group, from Lithium (Li) to Potassium (K)
• Alkali metals react similarly with water, producing effervescence and dissolving and begin to move around in the solution
• Sodium melts during its reaction and Potassium self-ignites with a lilac-colored flame
• Lithium reacts with water to produce Lithium Hydroxide and Hydrogen

Reactions With Acids

• Four metals (Ca, Cu, Mg, Zn) were reacted with a strong acid
• Calcium: violent fizzing, heats up, white solid forms
• Copper: No visible reaction
• Magnesium: effervescence, heats up, dissolves
• Zinc: Slight bubbles on surface
• Metals will only react with an acid if it is more reactive than hydrogen

Reactivity

• To determine the relative reactivity of elements, displacement reactions are carried out
• The more reactive metal will displace a less reactive one

Displacement Reactions

• Cu does not react with FeSO4, MgSO4, and ZnSO4
• Fe reacts with CuSO4 and displaces Mg and Zn
• Mg reacts with CuSO4, FeSO4 can displace Zn
• Zn reacts with CuSO4 and FeSO4

Oxidation and Reduction

• Oxidation and reduction are defined in terms of electrons
• Oxidation is the loss of electrons
• Reduction is the gaining of electrons
• In the example 2Fe2O3 + 3C → 4Fe + 3CO2, Iron is reduced because it gains 3 electrons

Extracting Metals

• Many metals exist in the earth's crust as ores
• An ore is a rock that contains enough compound worth extracting
• Very few metals are found in their native state, which means pure metal not bonded to anything
• Gold and platinum are examples of metals found in their native state because they are very unreactive
• How metals are extracted from their ores depends on their reactivity
• Metals less reactive than carbon are extracted by displacement using carbon
• The reaction Iron oxide → Iron + Carbon dioxide is known as reduction (removing O2)
• Elements more reactive than carbon are extracted using electrolysis

Magnesium reacts with oxygen, hydrochloric acid, and copper sulphate, each producing distinct results. Group 1 alkali metals increase in reactivity down the group, reacting vigorously with water. Calcium, Copper, Magnesium and Zinc react differently with strong acids.