1. Which of the following statements best describes an element?  I. a pure substance  II. can be separated   III. made of only one kind of atom   IV. a homogeneous mixture

2. Why do elements belonging to the same group have the same properties?

3. Where can we find the nonmetals in the periodic table?

4. An element belongs to group VI A and period 3 in the periodic table. Which of the following characteristics best describe this element?I. a nonmetal II. has 6 valence electrons and 3 main energy levels III. has 3 valence electrons and 6 main energy levels IV. can form -2 ion

5. Element X has this electron configuration: 1s2 2s2 2p6 3s2 3p6; to what group and period does this element belong?

6. Which of the following statements about the periodic table is true?I. Elements belonging to the same group have similar outer electron configurations.  II. Elements found in the same row have the same group number.  III. There are more metals than nonmetals in the periodic table.IV. Elements that are in the leftmost side of the periodic table end in s1 configuration while elements on the rightmost side end in p6

7. Based on electron configuration, the group and period number where element 15P is ___________.

8. Which type of element can exist as gas at room temperature?

9. The pair of elements in question number 1 will have similar outer electron configurations and chemical behaviors because _______________.