Practice Questions

Propose a reason why pure 24-carat gold is generally considered unsuitable for making jewellery.

Identify the non-metal that is known for its lustrous appearance.

Examine why ionic compounds like sodium chloride ($NaCl$) have high melting points.

Apply your knowledge of the reactivity series to predict if a reaction will occur when a strip of copper is placed in a solution of silver nitrate ($AgNO_3$).

Name the metal which is a liquid at room temperature and the non-metal which is a liquid at room temperature.

A student adds a zinc strip to a blue copper(II) sulphate solution. Formulate a balanced chemical equation for the reaction and justify why this reaction occurs with reference to the reactivity series. Predict two observable changes.

Recall what the reactivity series of metals represents.

Define the property of ductility in metals.

Define the term 'alloy' and give one common example.

Propose a chemical reason why alkali metals like sodium and potassium are stored under kerosene oil.

Explain why sodium metal is stored under kerosene oil.

List three uses of metals in daily life and name the specific property that makes them suitable for that use.

Explain why ionic compounds generally have high melting and boiling points.

Name the primary components of the alloy stainless steel.

Analyze why an aluminum pan, despite aluminum being more reactive than iron, is highly resistant to corrosion.

Examine why a solution of an ionic compound in water conducts electricity.

Apply the concept of amphoteric oxides to explain how aluminum oxide ($Al_2O_3$) can react with both sodium hydroxide ($NaOH$) and hydrochloric acid ($HCl$).

Compare the metallurgical processes of roasting and calcination. Provide one example for each with a balanced chemical equation.

Contrast the physical properties of diamond and graphite, both allotropes of carbon, in terms of hardness and electrical conductivity. Analyze how these properties relate to their atomic structure.

An element 'X' reacts with oxygen to form an oxide $X_2O$. A solution of this oxide in water turns red litmus paper blue. Analyze whether 'X' is a metal or a non-metal and justify your answer.

Evaluate the thermit reaction, involving iron(III) oxide ($Fe_2O_3$) and aluminium, for its industrial application. Justify why this specific reaction is highly suitable for welding railway tracks.

List and describe five general physical properties of metals.

Compare the reaction of magnesium and iron with water. Write balanced chemical equations for the reactions that occur and specify the conditions required for each.

Demonstrate the formation of magnesium chloride ($MgCl_2$) from its constituent elements using electron-dot structures. Analyze the type of bond formed.

Analyze the experimental setup designed to investigate the conditions for rusting. Explain the purpose of anhydrous calcium chloride in test tube C and the layer of oil in test tube B. What conclusion can be drawn from this experiment?

Design an experiment to compare the reactivity of zinc, iron, and copper with dilute hydrochloric acid. Justify your proposed methodology, state the expected observations, and formulate a conclusion that arranges these metals in decreasing order of reactivity.

Critique the statement: 'Ionic compounds conduct electricity in all physical states.' Justify your critique with reference to the structure and particle mobility in different states.

Create an electron-dot diagram to illustrate the formation of magnesium oxide ($MgO$). Justify the charges formed on the resulting ions based on their electronic configurations.

A student claims that all lustrous elements are metals. Critique this statement by providing a specific counter-example and justify why physical properties alone are often insufficient for classifying elements.

Formulate a general plan to extract a moderately reactive metal like zinc from its sulphide ore, zinc blende ($ZnS$). Your plan should outline the main metallurgical steps and name the processes involved.

You are given three unlabelled metal samples: Magnesium, Aluminium, and Iron. Design a simple test using only a beaker of hot water to identify the magnesium sample. Justify your reasoning.

Justify the choice of zinc over tin for galvanising an iron object that will be used outdoors.

Describe the reaction of the following metals with water: (i) Potassium, (ii) Calcium, and (iii) Iron. Include chemical equations.

Compare and contrast the reaction of sodium, calcium, and aluminum with water under different conditions. Write balanced chemical equations for all reactions that occur and analyze the reasons for their differing reactivity.

What are amphoteric oxides? Give one example and write the chemical reactions to support your answer.

Summarize the key difference between the metallurgical processes of roasting and calcination.

Evaluate the use of galvanisation versus painting as methods for preventing the rusting of an iron gate. Justify which method provides more durable protection, especially if the surface gets scratched.

Describe the process of electrolytic refining of an impure metal such as copper. Identify what is used as the anode, cathode, and electrolyte.

Aqua regia is a mixture capable of dissolving noble metals like gold. Propose a chemical explanation for why this mixture is effective where individual acids fail, and formulate the role of each acid component.

Design the setup for the electrolytic refining of an impure copper block. Your design must specify the materials for the anode, cathode, and electrolyte. Propose the chemical reactions that occur at each electrode.

An ore is identified as a carbonate of metal M ($MCO_3$), where M is a highly reactive metal like calcium. Propose a complete, multi-step metallurgical process to extract pure metal M. Justify your choice of methods, explaining why reduction with carbon is not feasible.

A student is given samples of zinc, copper, iron, and magnesium. Analyze how they would arrange these metals in decreasing order of reactivity by reacting them with a solution of iron(II) sulphate ($FeSO_4$). Explain the expected observations and write the relevant chemical equations for the displacement reactions.

A metal 'M' is moderately reactive and exists as a sulphide ore ($MS$). Solve the steps required to extract this metal from its ore. Write the general equations for the reactions involved.

You are tasked with the electrolytic refining of an impure copper block. Demonstrate the setup by identifying what you would use for the anode, the cathode, and the electrolyte. Explain the chemical processes that occur at both electrodes.