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Question
An element has its electron configuration as 2,8,8,2. Now answer the following questions.
a) What is the atomic number of this element?
b) What is the group of this element?
c) To which period does this element belong?
Solution
a) The atomic number of this element is 20.
b) The group of this element 2.
c) This element belongs to fourth period.
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\[\ce{MnO2(s) + Al(s) -> Mn(l) + Al2O3(s) + Heat}\]
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