I believe it has something to do with the H2O molecules, because a chemical compound is not a mixture.
The molecular geometry is trigonal bipyramidal.
Ight even though you have to answer other peeps
The atomic cation with +1 charge with the following configuration:
1s22s22p63s23p6
Is Potassium (K+), remember potassium have 19 electrons in its neutral state, when if losses one electrons it becomes + with one less electron, meaning it will have 18 electrons as a cation.
There are 2 electrons in 1s orbital as it can be seen from the electron configuration.
Option 2, Br. I'll go over why all other three options are incorrect.
Option 1 - Krypton is a Noble gas, and so it doesn't need to accept electrons since it has an octet.
Option 3 and 4 - Both Calcium and Barium are alkaline earth metals, and give away electrons, since they only have 2.
-T.B.
