9.6. Extraction of metals
A subsection of Chemistry, 0620, through 9. Metals
Listing 10 of 311 questions
A student investigates the reaction of calciumcarbonate with dilute hydrochloricacid. CaCO3 + 2HCl CaCl 2 + CO2 + H2O The student measures the mass of the reaction mixture at 10 second intervals using the apparatus shown. 250.00 g calcium carbonate cotton wool dilute hydrochloric acid The graph shows the results when 5.0 g of calciumcarbonate is added to an excess of dilute hydrochloricacid. time / s mass / g Suggest why the reaction mixture decreases in mass as the reaction proceeds. Calculate the loss of mass in grams when the reaction is complete.  loss in mass = g The experiment is repeated using dilute hydrochloricacid of twice the concentration. All other conditions are kept the same. On the grid, draw a graph to show how the mass changes with time using dilute hydrochloricacid of twice the concentration. The original experiment is repeated at three different temperatures. All other conditions are kept the same. The three temperatures are 20 °C, 30 °C and 40 °C. Complete the table by writing the temperatures in the first column. temperature in °C initial rate of reaction in g / s 0.16 0.64 0.32  Complete the sentences about the use of calciumcarbonate in the extraction of iron using words from the list. bauxite dioxide hematite monoxide silicon slag The main ore of iron is called . The main impurity in the iron ore is silicon(oxide. Calcium carbonate added to the blast furnace decomposes to form calcium oxide and carbon . The calcium oxide reacts with the silicon(oxide to form .  
0620_w18_qp_31
THEORY
2018
Paper 3, Variant 1
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A student investigates the rate of reaction of iron powder with dilute hydrochloricacid. dilute hydrochloric acid iron powder Complete the diagram to show the apparatus the student could use to collect and measure the gas produced. Label your diagram. The graph shows the results the student obtained using dilute hydrochloricacid of concentration 0.2 mol / dm3 and an excess of iron powder. time / minute volume of gas / cm3 Use the graph to deduce: the time that the reaction was complete the volume of gas produced when the reaction was complete. The student repeated the experiment using a lower concentration of dilute hydrochloricacid. All other conditions were kept the same. On the grid, draw a graph to show how the volume of gas changes with time when a lower concentration of dilute hydrochloricacid is used. Iron is extracted from iron ore using a blast furnace. The solid substances added to the blast furnace are iron ore, coke and limestone (calciumcarbonate). State the name of an ore of iron. Complete the sentences about the reactions which occur in a blast furnace using words from the list. air decomposes dioxide monoxide nitrogen oxidises slag tetrachloride The coke burns in a blast of hot to form carbondioxide. This reacts with further hot coke to form carbon . This gas reduces the iron(oxide in the iron ore to iron. The limestone to form lime (calciumoxide) which reacts with impurities in the iron to form .  
0620_w18_qp_33
THEORY
2018
Paper 3, Variant 3
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Questions Discovered
311