Question 1: Define a metal and a non-metal, highlighting two key differences.

Answer: A metal is a good conductor of electricity and is malleable; a non-metal is a poor conductor and brittle.

Question 2: Explain why metals tend to lose electrons during chemical reactions, whereas non-metals tend to gain electrons.

Answer: Metals have a low ionisation energy, so they easily lose electrons to form positive ions; non-metals have high electronegativity, so they tend to gain electrons to complete their outer shells.

Question 1: Calculate the number of moles in 12 grams of aluminium. (Atomic mass of Al = 26.98 g/mol)

Answer: Number of moles = mass / molar mass = 12 g / 26.98 g/mol ≈ 0.444 mol

Question 2: A sample contains 3.01 x 10^23 atoms of sulphur. How many moles of sulphur are present? (Atomic mass of S = 32.07 g/mol)

Answer: Number of moles = atoms / Avogadro's number = 3.01 x 10^23 / 6.022 x 10^23 ≈ 0.5 mol

Question 1: Describe a simple experiment to test whether a substance is a metal or a non-metal based on electrical conductivity.

Answer: Connect the substance to a circuit with a light bulb; if the bulb lights up, the substance conducts electricity and is likely a metal; if not, it is likely a non-metal.

Question 2: List two safety precautions that should be taken when handling acids to test metal reactivity.

Answer: Wear safety goggles and gloves to protect against splashes; work in a well-ventilated area.

Question 1: A metal sample reacts vigorously with hydrochloric acid, producing hydrogen gas. What does this indicate about the metal's reactivity and position on the periodic table?

Answer: It indicates the metal is highly reactive, likely an alkali or alkaline earth metal, and is positioned towards the left and top of the periodic table.

Question 2: A non-metal sample is found to be a poor conductor of electricity and has a dull appearance. Based on these observations, suggest its possible element category and typical properties.

Answer: It is likely a non-metal, with properties such as poor electrical conductivity, dull appearance, and tendency to be brittle.

Question 1: Explain why metals are generally good conductors of electricity, while non-metals are not.

Answer: Metals have free electrons in their outer shells that can move easily, allowing electric current to pass through. Non-metals lack these free electrons, making them poor conductors.

Question 2: Discuss the industrial importance of metals like aluminium and non-metals like sulphur, including their common uses.

Answer: Aluminium is lightweight, corrosion-resistant, and widely used in packaging, aircraft, and construction. Sulphur is used in the manufacture of sulphuric acid, fertilisers, and vulcanisation of rubber, highlighting its importance in industry.