10 questions ยท Form 3 Science Bab 4: Reactivity of Metals
Which of the following metals can be extracted from its oxide ore by reduction using carbon powder?
Prefer reading to quizzing? All 10 questions are listed below with the answer and explanation under each one.
1. Which of the following metals can be extracted from its oxide ore by reduction using carbon powder?
Answer: C
Tin ($Sn$) is situated below Carbon in the reactivity series, meaning Carbon can reduce tin oxide to tin metal.
2. Which environmental impact is directly associated with roasting sulfide ores during metal extraction?
Answer: A
Roasting sulfide metal ores releases sulfur dioxide gas ($SO_2$), which dissolves in rainwater to form acid rain.
3. Which reagent is used to confirm the presence of carbon dioxide gas emitted during a reaction?
Answer: B
Carbon dioxide gas reacts with clear limewater (calcium hydroxide) to produce insoluble calcium carbonate precipitate, making the limewater cloudy.
4. What term describes naturally occurring solid chemical elements or compounds found in Earth's crust?
Answer: B
Minerals are inorganic elements or compounds found naturally with specific crystalline structures in the Earth's crust.
5. Where is Hydrogen positioned in the Reactivity Series of Metals?
Answer: B
Dry hydrogen gas reduces iron oxide to iron when heated, but cannot reduce zinc oxide, placing Hydrogen between Zinc and Iron.
6. What are the chemical elements present in the mineral galena?
Answer: B
Galena is chemically known as lead(II) sulfide ($PbS$), which consists of lead and sulfur.
7. Which of the following minerals exists in an uncombined elemental state in the Earth's crust?
Answer: C
Gold is a very unreactive metal, so it exists naturally as a free element rather than as a chemical compound.
8. What products are formed when calcium carbonate ($CaCO_3$) is heated strongly?
Answer: B
Thermal decomposition of calcium carbonate yields solid calcium oxide (quicklime) and carbon dioxide gas: $CaCO_3 ightarrow CaO + CO_2$.
9. What is the chemical reaction when dilute hydrochloric acid is added to marble chips?
Answer: A
Marble chips (calcium carbonate) react with dilute acid to produce a soluble salt, water, and carbon dioxide gas.
10. Predict what happens when dry hydrogen gas is passed over strongly heated aluminium oxide powder.
Answer: B
Aluminium lies higher than Hydrogen in the reactivity series, so Hydrogen is unable to reduce aluminium oxide.