What are the first 20 elements of the periodic table and information about them?

Here they are listed by atomic number, element name and chemical symbol:

1 Hydrogen H

2 Helium He

3 Lithium Li

4 Beryllium Be

5 Boron B

6 Carbon C

7 Nitrogen N

8 Oxygen O

9 Fluorine F

10 Neon Ne

11 Sodium Na

12 Magnesium Mg

13 Aluminum Al

14 Silicon Si

15 Phosphorus P

16 Sulfur S

17 Chlorine Cl

18 Argon Ar

19 Potassium K

20 Calcium Ca

Use the link below to a list of all the chemical elements by atomic number. It's to the Wikipedia post, and each element is a hyperlink to the post on that element. Bookmark this bad boy, and the periodic table of elements at Wikipedia, too. The periodic table there is interactive, just like this list. And both are a boon to the study of school chemistry. Bookmark them for 30 days and try them out. You can always dump them later, but the benefits you'll derive in just one use will verify their worth. Promise.