Chapter 3, Problem 3.8E

Based on the periodic table, the elements are arranged in the order of their atomic numbers, according to the horizontal and vertical series. The average distance between the nucleus and the outside electrons, as well as the effective nuclear charge experienced by these electrons, are responsible for many of the features of atoms. a. What is meaning of the term atomic radius? b. As you move, what trend in atomic radius do you notice? i. from left to right across a row in the periodic table. Explain the trend. ii. from top to bottom in a group in the periodic table. Explain the trend. c. Arrange the atoms [P, F, S, and As] in increasing atomic radius order.

What property did Mendeleev have that allowed him to put the elements in a pretty good order from lowest to highest and what was the first element where we found a problem with the patterns and had to switch them around a bit? What is a periodic property? Describe and give an example.

Look up the density of silicon and of lead in a table online. Then look up the atomic radius of silicon and lead . Then look up the atomic mass of each element (periodic table of elements). Use the atomic mass and atomic radius of each element to make an argument about density. Based on the atomic radii and atomic mass data, which element would be the most dense. Is that expectation consistent with actual density data? Use the definition of density to support your argument.