Using a broom to clean sidewalks and driveways is a way to reduce water pollution.

1) how many electrons are in each energy level of the following elements? a. he b. na c. na d. ne 2) how many valence electrons are percent in the following atoms? a. s b. mg c. be d. cl 3) which of the following elements are stable as atoms? a. he b. o c. cl d. ar if you are able to provide the work as to how you got the answers that would be greatly appreciated. : )

What are the similarities of physical and chemical change ?

Name the element in group 17, period 2. (periodic table)