Question

PRE-LAB 1. Who is the father of our modern periodic table? 2. What are the horizontal rows on the periodic table called? What are the columns called? 3. Which row(s) or column(s) represents the halogens? 4. Which row(s) or column(s) represents the transition metals? 5. Give an example of a metal that is liquid at room temperature 6. Which row(s) or column(s) represent the alkali metals? 7. Which row(s) or column(s) represent the alkaline earth metals? 8. Give an example of a halogen that is liquid at room temperature. 9. Give an example of a non-reactive gas. 10. What are the characteristics of a metalloid?

Answer 1

1. Dmitri Mendeleev is recognized as the father of modern periodic table.

2. Horizontal rows are called periods and the columns are called groups in the periodic table.

3. Elements present in group number 17 are called halogens. So, the halogens are represented by the elements of group 17.

4. The transition elements are represented by elements of group 3 to group 12 and period 4 to period 6.

5. Mercury, Hg is a metal that is liquid at room temperature.

6. The elements of group 1 are called alkali metals. So, the alkali metals are represented by group 1.

7. The elements of group 2 are called alkaline earth metals. So, the alkaline earth metals are represented by group 2.

8. Halogen that is liquid at room temperature is Bromine, Br.

9. Elements of group 18 are called noble gases. They are highly stable unreactive gases. Examples are helium (He), Neon (Ne), Argon (Ar) etc.

10. Metalloids are elements which show both metallic as well as non metallic character. Characteristics of metalloids are:

• Metalloids show properties which are intermediate between metals and non metals.
• Metalloids are solid at room temperature.
• Metalloids have low elesticity.
• Many metalloids such as silicon, germanium are used as semiconductors in electronic devices.
• Metalloids are used in making alloys with other metals.