Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Metallic Bonding: Metals consist of a giant lattice of positive metal ions () surrounded by a 'sea' of delocalized electrons. These electrons are free to move, making metals excellent conductors of electricity and heat.
Physical Properties: Metals are generally malleable (can be hammered into sheets) and ductile (can be drawn into wires) because the layers of ions can slide over each other without breaking the metallic bond.
Chemical Properties - Reaction with Oxygen: Most metals react with oxygen to form basic metal oxides. For example: .
Chemical Properties - Reaction with Water: Reactive metals (like Group 1) react with cold water to form a metal hydroxide and hydrogen gas: .
Chemical Properties - Reaction with Acids: Metals above hydrogen in the reactivity series react with dilute acids to produce a salt and hydrogen gas: .
Reactivity Series: A list of metals arranged in order of decreasing reactivity (). It determines which metal can displace another from its compound.
Displacement Reactions: A more reactive metal will displace a less reactive metal from its salt solution. For example, .
Alloys: Mixtures of a metal with other elements (e.g., Brass is and ). Alloys are harder than pure metals because atoms of different sizes disrupt the regular lattice, preventing layers from sliding easily.
📐Formulae
💡Examples
Problem 1:
Predict the products and write a balanced equation for the reaction between Aluminum () and Iron(III) oxide ().
Solution:
Explanation:
This is a thermite reaction. Aluminum is more reactive than Iron in the reactivity series, so it displaces Iron from its oxide. The reaction is highly exothermic, often producing molten iron.
Problem 2:
Explain why Copper () does not react with dilute Sulfuric acid ().
Solution:
No reaction occurs.
Explanation:
Copper is lower than Hydrogen in the reactivity series (). Therefore, Copper is not reactive enough to displace Hydrogen ions () from the acid solution.
Problem 3:
What is observed when a piece of Calcium () is added to a beaker of cold water?
Solution:
Explanation:
Observations include effervescence (bubbles of gas), the metal dissolving/disappearing, and the formation of a cloudy white suspension of as it is only sparingly soluble.