The chemical element in group one that is also a member of period 2 is lithium.
The chemical element in group one that is also a member of period 2 is lithium therefore, the element referred to here is lithium. Group 1 has only one valence electron. If we add one to 23, we will have 24 and the element is chromium.
For question three, the focus is on period 5, five groups to the previous answer will give us the element molybdenum. The atomic number of Mo is 42 and its mass number 96 hence it has 54 neutrons. The element that has atomic number 54 is Xe.
The element that has atomic mass 43 which is reversal of the atomic number of the former answer is scandium.
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