本题目来源于试卷: Classification of Matter A.1 Periodic Table Elements Classification，类别为 IB化学
[单选题]
Which of the following elements has the mxaz swi5z .ybyew4 9(c-s (i;h4 aaxmw, 4azx llw73i1ighest first ionization energy?
A. Sulfur
B. Magnesium
C. Oxygen
D. Beryllium
参考答案: C
本题详细解析:
Explanation: First ionization energy decreases down a group due to increased shielding (number of shells). Beryllium must therefore have a higher first IE than magnesium. And similarly, oxygen higher than sulfur.
First ionization energy increases across a period due to increased nuclear charge for the same number of shells. Hence, oxygen has higher first IE than beryllium.
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