add ammonia. Chloride ions-dissolve in dilute ammonia. Bromide ions-dissolve in conc ammonia. Iodide ions-insoluble in conc ammonia.
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what is the trend in atomic radius for group 2 elements?
decreases down group due to extra electron shells
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what is the trend in ionisation energy for group 2 elements?
decreases down group due to extra electron shells providing shielding. Reduces nucleus attraction to outer electrons.
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what is the trend in reactivity for group 2 elements?
increases down the group, the easier it is to lose electrons, the more reactive the element
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what is the trend in melting point for group 2 elements?
decreases down the group. Group 2 elements have metallic structures with their outer shell electrons being delocalised. Going down the group the ions get bigger
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what's the reaction of group 2 compounds with water?
M+2H2OM(OH)2+H2, Elements react more readily down the group due to the ionisation energies decreasing
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what are barium metals used for in medicine?
Barium sulphate used in meals to diagnose problems with the oesophagus, stomach or intestines. Patient swallows barium sulphate which coats the tissues so they show up on the X-rays.
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why can you only use barium sulphate in medicine?
other barium solutions are poisonous
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what is an ore?
natural substance a metal can be extracted from
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how do you extract aluminium?
Using electrolysis- ore is Al2O3 with various impurities. 1st impurities removed then dissolved in Na3AlF6 which lowers m.p. Cathode:Al3++3e-Al. Anode:2O2-O2+4e-.
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how do you extract titanium?
TiO2+2Cl2+2CTiCl4+2CO. TiCl4 purified by fractional distillation. Chloride reduced in furnace at 1000oc. TiCl4+4NaTi+4NaCl.TiCl4+2MgTi+2MgCl2
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what are the advantages of recycling metals?
Saves raw materials-ores finite resource. Saves energy-use less energy than metal extraction. Saves money to. Reduces waste sent to landfill. Reduces damage to landscape.
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what are the disadvantages of recycling metals?
Collecting and sorting metals from other waste can be difficult and expensive.Purity of recycled metal varies-usually other metals and impurities mixed in. Recycling may not produce consistent supply to meet demand.
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Other cards in this set
Card 2
Front
what is an oxidising agent?
Back
accept electrons and get reduced
Card 3
Front
what is a reducing agent?
Back
Card 4
Front
what do oxidation states do?
Back
Card 5
Front
what is the trend in boiling points of the halogens?
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