<u>Answer:</u> The correct answer is Strontium.
<u>Explanation:</u>
Reactivity of an element is defined as the tendency to loose or gain electrons. Reactivity decreases as we move from left to right in a period and it increases as we move from up to down in a group.
A metal which belongs to Period 5 and has 2 valance electrons is Strontium. This element belongs to Group 2.
The electronic configuration of strontium (Sr) =
Hence, the correct answer is Strontium.
Answer:
n=1 holds two electrons and n=2 holds eight electrons.
Explanation:
Hello
In this case, since the atomic number of aluminum is 13, its electron configuration is:
In such a way, we can see that the level n=1 is filled with two electrons since the subshell s is able to hold two electrons and the level n=2 is also filled but with eight electrons as s holds two whereas p holds 6. Moreover, n=3 is holding three electrons.
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