Explain why a solution that is 1.3 M HF and 1.3 mM KF is not a good buffer. HF is a strong acid and cannot be used in a buffer system. The ratio of acid to conjugate base is outside the buffer range of 10:1. KF is not soluble in water and cannot be used in a buffer system. The two species are not a conjugate acid base pair.

it's c. elements are placed in rows based on how may valencies electrons have.

bcde is the incorrect answer it is a

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.