Why can't elements be separated into smaller parts using chemical means? Too much energy is required, since you'd have to break them down into protons, neutrons, and electrons. You can get this much energy together with nuclear reactions, but not by chemical means.
alkali metals are the most reactive family
they are located in column 1 on the periodic table
I am sure it is a.12150sn and 11950sn because isotopes are the same atoms but different number of protons
