idkmkk
5 5s equals 25.
5/5=1 Keep this for later. so 2 5s used. Then do 5*5=25, so 5 5s used as 25 has a five in it, now do 1 - 25=24.
21 5s
22 5s - 3 = 5(5) - 3 = 25-3 = 22
In the Rb atom, the electron configuration is [Kr]5s^1. This means there is 1 electron in the 5s sublevel of the Rb atom.
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