Question 1: Define an ionic bond and explain how it forms between a metal and a non-metal.

Answer: An ionic bond is a strong electrostatic attraction between oppositely charged ions, formed when a metal atom loses electrons to become a positive ion (cation) and a non-metal gains electrons to become a negative ion (anion).

Question 2: Describe the process by which sodium and chloride ions form an ionic compound.

Answer: Sodium atom loses one electron to become Na⁺, and chloride atom gains that electron to become Cl⁻. The electrostatic attraction between Na⁺ and Cl⁻ results in an ionic bond, forming sodium chloride (NaCl).

Question 1: Calculate the number of electrons transferred when magnesium reacts with oxygen to form an ionic compound.

Answer: Magnesium loses 2 electrons to form Mg²⁺, and oxygen gains 2 electrons to form O²⁻. So, 2 electrons are transferred per magnesium atom.

Question 2: Determine the empirical formula of an ionic compound formed between aluminium ions (Al³⁺) and sulphate ions (SO₄²⁻).

Answer: The smallest whole number ratio of Al³⁺ to SO₄²⁻ ions is 2:3, giving the formula Al₂(SO₄)₃.

Question 1: Describe a simple experiment to demonstrate the formation of an ionic compound in a laboratory setting, including safety precautions.

Answer: A student could react sodium metal with chlorine gas in a fume cupboard to produce sodium chloride. Safety precautions include wearing gloves, goggles, and working in a well-ventilated area or fume cupboard due to the toxic nature of chlorine gas and reactive sodium. The formation can be observed through the release of heat and the formation of white crystalline NaCl.

Question 2: Identify the variables that would affect the formation of ionic bonds in a controlled experiment.

Answer: Variables include the type of metal and non-metal used, temperature, concentration of reactants, and the presence of catalysts or impurities.

Question 1: A sample contains a mixture of sodium chloride and magnesium oxide. Explain how the ionic bonds differ between these compounds based on their formation.

Answer: NaCl forms from Na⁺ and Cl⁻ ions with a 1:1 ratio, while MgO forms from Mg²⁺ and O²⁻ ions with a 1:1 ratio but involves a magnesium ion losing 2 electrons and oxygen gaining 2 electrons, resulting in different bonding strengths and properties.

Question 1: Explain why ionic compounds tend to have high melting points.

Answer: Ionic compounds have high melting points because the electrostatic forces of attraction between oppositely charged ions are very strong, requiring a large amount of energy to break these bonds during melting.

Question 2: A compound is found to contain 40% sodium and 60% chlorine by mass. Calculate its empirical formula.

Answer: Mass of Na: 40 g, Moles of Na: 40 g / 23 g/mol ≈ 1.74 mol. Mass of Cl: 60 g, Moles of Cl: 60 g / 35.5 g/mol ≈ 1.69 mol. Ratio close to 1.74:1.69 ≈ 1:1, so empirical formula is NaCl.

Question 1: Describe how knowledge of ionic bonding is utilised in the manufacture of batteries or electronic devices.

Answer: Ionic bonding principles are used in battery electrolytes and semiconductors, where the movement of ions enables electrical conductivity, crucial for battery function and electronic components.