Can someone help me with this? :(

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. : )

Write the complete balanced equation for the reaction between lead (iv) oxide (pbo2) and water (h2o).

The name of the ion, s2-, is: sulfurous ion sulfide ion sulfur ion sulfate ion