1.22 Chlorofluorocarbons damage the ozone layer by undergo…
1.22 Chlorofluorocarbons damage the ozone layer by undergoing reactions with a free radical mechanism. The first stage of this is initiation. Which equation is most likely to be the initiation stage when chlorofluoromethane is involved in such a reaction? (1) Right-click on the button to open the data booklet in a new tab.
Read Details1.15 A piece of rock has a mass of 2.00 g. It contains ca…
1.15 A piece of rock has a mass of 2.00 g. It contains calcium carbonate, but no other basic substances. It neutralises exactly 36.0 cm3 of 0.500 mol.dm–3 hydrochloric acid. What is the percentage of calcium carbonate in the 2.00 g piece of rock? (1)
Read Details1.12 Elements D and E are both in Period 3. Element D has…
1.12 Elements D and E are both in Period 3. Element D has the smallest atomic radius in Period 3. There are only two elements in Period 3 which have a lower melting point than element E. Elements D and E react together to form compound L. (1) Which compound could be L A MgCl2 B MgS C Na2S D PCl 3
Read Details1.19 When solid ammonium chloride dissociates at a certain…
1.19 When solid ammonium chloride dissociates at a certain temperature in a 0.500 dm3 container, ammonia and hydrogen chloride are formed. NH4Cl (s)< == > NH3(g) + HCl (g) The initial amount of ammonium chloride was 1.00 mol, and when the system had reached equilibrium there was 0.300 mol of ammonium chloride. What is the numerical value of Kc for this reaction under these conditions? (1)
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