91Ó°ÊÓ

On what basis did Mendeleev construct his periodic table? On what basis are the elements arranged in the modern periodic table?

Using their positions in the periodic table, explain why is it not surprising that strontium-90, a radioactive isotope, replaces calcium in newly formed bones.

Why would you reasonably expect cadmium to be a contaminant in zinc but not in silver?????

Using the symbol for nitrogen, \({ }_{7}^{14} \mathrm{~N}_{2}^{0},\) indicate what information is conveyed by the two superscripts, and what information is conveyed by the two subscripts.

Make a rough sketch of the periodic table and mark off those areas where you would find (a) the representative elements, (b) the transition elements, and (c) the inner transition elements.

Which of the following is (a) an alkali metal? Ca, \(\mathrm{Cu}\), In, \(\mathrm{Li}, \mathrm{S}\) (b) a halogen? Ce, \(\mathrm{Hg}, \mathrm{Si}, \mathrm{O}, \mathrm{I}\) (c) a transition element? \(\mathrm{Pb}, \mathrm{W}, \mathrm{Ca}, \mathrm{Cs}, \mathrm{P}\) (d) a noble gas? \(\mathrm{Xe}, \mathrm{Se}, \mathrm{H}, \mathrm{Sr}, \mathrm{Zr}\) (e) a lanthanide element? \(\mathrm{Th}, \mathrm{Sm}, \mathrm{Ba}, \mathrm{F}, \mathrm{Sb}\) (f) an actinide element? Ho, \(\mathrm{Mn}, \mathrm{Pu},\) At, \(\mathrm{Na}\) (g) an alkaline earth metal? \(\mathrm{Mg}, \mathrm{Fe}, \mathrm{K}, \mathrm{Cl}, \mathrm{Ni}\)

Name five physical properties that we usually observe for metals.

Which physical property of metalloids distinguishes them from metals and nonmetals?

Most periodic tables have a heavy line that looks like a staircase starting from boron down to polonium. What information does this line convey?

What is the difference between an atom and a molecule?