Properties of Metals and Reactivity Series

Properties of Metals

• Metals are good conductors of heat and electricity.
• Metals are malleable (can be hammered into shape) and ductile (can be drawn into wires).
• Metals are usually shiny and lustrous.
• Metals are typically solid at room temperature (except for mercury).
• Metals have a high density compared to non-metals.

Reactivity Series

• The reactivity series is a list of metals arranged in order of their decreasing reactivity.
• Potassium (K) is the most reactive metal, followed by sodium (Na), lithium (Li), calcium (Ca), magnesium (Mg), aluminium (Al), zinc (Zn), iron (Fe), lead (Pb), copper (Cu), silver (Ag) and gold (Au).

Metals and Water

• Highly reactive metals (K, Na, Li, Ca) react vigorously with cold water, producing hydrogen gas and a metal hydroxide.
• For example, sodium reacts with water to produce sodium hydroxide and hydrogen gas:

2Na + 2H₂O → 2NaOH + H₂

• Less reactive metals (Mg, Al) react with steam (water vapor) to produce a metal oxide and hydrogen gas.

Mg + H₂O → MgO + H₂

• Metals below hydrogen in the reactivity series (Zn, Fe, Pb, Cu, Ag, Au) do not react with water.

Metals and Oxygen

• All metals react with oxygen to form metal oxides, but the reactivity varies.
• Highly reactive metals react quickly with oxygen at room temperature, whereas less reactive metals require heating.
• For example, iron reacts with oxygen to form iron oxide (rust):

4Fe + 3O₂ → 2Fe₂O₃

Metals and Acids

• Metals higher than hydrogen in the reactivity series react with acids to produce a salt and hydrogen gas.
• For example, zinc reacts with hydrochloric acid to produce zinc chloride and hydrogen gas:

Zn + 2HCl → ZnCl₂ + H₂

• Metals below hydrogen in the reactivity series do not react with acids.

Displacement Reactions

• A displacement reaction occurs when a more reactive metal displaces a less reactive metal from its compound.
• For example, if a piece of zinc is added to a solution of copper sulfate, the zinc will displace the copper:

Zn + CuSO₄ → ZnSO₄ + Cu

Word Equations

• Word equations describe chemical reactions using the names of the reactants and products.
• For example, the reaction of zinc and copper sulfate can be written as:

Zinc + Copper Sulfate → Zinc Sulfate + Copper

Chemical Equations

• Chemical equations use chemical symbols and formulas to represent chemical reactions.
• For example, the reaction of zinc and copper sulfate can be written as:

Zn + CuSO₄ → ZnSO₄ + Cu

Balancing Chemical Equations

• Balancing chemical equations ensures that the number of atoms of each element is the same on both sides of the equation.
• To balance an equation, coefficients are added in front of the chemical formulas.
• For example, the balanced equation for the reaction of zinc and copper sulfate is:

Zn + CuSO₄ → ZnSO₄ + Cu