Figure 5-1 shows a portion of a blank periodic table. identify the segments labeled a and b. a. a and b are both periods. b. a is a period and b is a group. c. a and b are both groups. d. a is a group and b is a period.

I believe that you forgot to add the figure. However, I'll tell you the difference between the period and the group in the periodic table and you can use these definitions to get the correct answer.

Periods: Each row in the periodic table is called a period (from left to right). Elements of the same period have exactly the same number of atomic orbitals. As you move down the table, each row (period) adds a new atomic orbital. Since the maximum number of orbitals discovered is seven, therefore, you will find that we have seven periods in the periodic table.

Groups: Each vertical column in the periodic table is called a group (from up to down). Elements of the same group have the same number of electrons in the valence shell with the exception of transition elements.