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(i) Energy required by an element to lose one electron in its outermost energy level in the gases state.
(ii) After losing the first electron the remaining electrons are firmly attracted by same number of protons hence require more energy for the second electron to be lost.
(iii) 420 + 3100 + 4800
= 8320KJ
sharon kalunda answered the question on March 27, 2019 at 08:13
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