Answer:
When metals react they lose electrons.
Explanation:
An ion is defined as a molecule or atom made up of a different number of electrons and protons. This makes the electric charge of the molecule net, not neutral.
In other words, an ion is a molecule or atom that has a positive or negative electric charge, making it an atom whose electric charge is not neutral.
The characteristic property of a metallic atom is to lose one or more of its electrons to form a positive ion. That is, metals lose electrons and acquire a net positive charge, which is why they are electropositive.
True would be your answer
A. cesium. bacause as the elements go down a group of the atoms, the sizes of the atom will increase . we know that tge tendency to lose an electron is based on the sizes of the atoms of group 1.
I believe the most harmful substance would be element C, this is because element C has a very long half life therefore it has a very slow rate of a decay. Half life of a substance it the time taken for substance to decay to half its original mass or amount.