Question

magine your homework assignment involves identifying an unknown pure substance. The valence electrons of the substance's atoms feel an effective nuclear charge of +1. If this substance's atoms have larger radii than potassium (K) atoms, what other characteristics would you expect the substance to exhibit?

Answer 1

It would be a very active (electropositive) metal. The low effective nuclear charge and very large radius (few atoms are as large as potassium) mean the valence electron(s) would be very loosely bound. So it would react violently with water to produce a basic oxide, the oxide itself would react with CO2 so that it would be found on Earth as a carbonate, it would be low melting, soft, conduct electricity and heat well, form ionic compounds with halogens and chalcogens, function as an excellent reducing agent and probably could be used to reduce less active metals like Fe, Cu, Ni, Zn.