![]() ![]() ![]() What this means is that the atomic and ionic radii and first ionisation energies don't change much across a transition series. state that the atomic radii, ionic radii and first ionisation energies of the transition elements are relatively invariant". The statement in the transition elements part of that syllabus said: "Candidates should be able to. He also asked: "Like atomic radius and ionization energy, does ionic radius (for some particular charge, say 2+) follow the same pattern as atomic radius?" is the ionization energy of zinc higher?" He wanted to know: "Zinc's atomic radius is 0.137nm while copper's is 0.128 nm (taken from my A level text). It came from a CIE (Cambridge International) A level student who had thought more carefully about a particular topic than was good for him! This question is a good example of a conscientious student trying to read more into a syllabus statement than is really there. If you are a student looking for reliable information about the topic, go somewhere else! If you aren't confident about your chemistry, go somewhere else!Ītomic and ionic radii compared with ionisation energies for the first transition series Very pure zinc may be formed from crude zinc by zone refining and single crystals can be grown with purities of better than 99.9999%.Important: If you have come straight to this page via a search engine, you should be aware that this is one of a number of pages dealing with e-mail questions that I haven't been able to answer to my satisfaction. Electrolysis of the ZnSO 4 solution using aluminium cathodes and lead alloyed with silver anodes gives pure zinc metal coated on the aluminium. Cadmium is an impurity and this is removed as a precipitate of cadmium sulphate by the addition of zinc dust. Dissolution of crude zinc oxide, ZnO, in sulphuric acid gives zinc sulphate, ZnSO 4 in solution. The other type of extraction is electrolytic. This may be reduced with carbon to form zinc metal, but in practice ingenious technology is required to ensure that the resulting zinc does not contain oxide impurities. These are roasted in industrial plants to form zinc oxide, ZnO. Most zinc production is based upon sulphide ores. Isolation: zinc metal is readily available commercially so it is not normally necesary to make it in the laboratory. Finally Zn-70 is also used in biological research and in research into super-heavy elements. Zn-66 has been proposed as an alternative target for the production of Cu-64 and Ga-67. Zn-67, Zn-68 and Zn-70 can all be used for the production of the therapeutic isotope Cu-67. However, by far most Ga-67 is made from Zn-68. It can also be used for the production of radioactive Ga-67 in smaller cyclotrons. Enriched Zn-67 is often used in biological research into the uptake of Zn in the human body. Neutron irradiation of Co-59 will result in the formation of Co-60, a radioisotope which emits high energy gamma radiation and is a major contributor to the dose rate of personnel working in the reactor. It also reduces the release of (stable) Co-59 into the cooling water by forming a thin spinel layer on the Co containing steel surfaces. Depleted Zn-64 is added to the cooling water of nuclear reactors in the form of oxide or acetate to prevent stress corrosion cracking. Zinc isotopes are used extensively in both industrial and medical applications. Isotope abundances of zinc with the most intense signal set to 100%. ![]()
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