Answers

2015-11-24T20:41:05+08:00
B. Magnesium

Magnesium is at the Group 2 of the periodic table and it belongs to Alkali Earth Metals and those elements in that group are so reactive. 
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2015-11-25T10:22:11+08:00

Mg, Fe, then Ag- Mg is the most reactive and least is Ag this is based on the activity series of metals
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