Determine the highest occupied energy level in the following elements:
a. He
b. Be
C. Al
d. Ca
e. Sn

What are fossils of organisms that existed over a wide area but only for a limited time period called?

1. list the number of drops of titrant needed to produce a color change for sample a and sample b. list the actual volume of titrant needed to produce a color change for sample a and sample b.

Which expression can be used to calculate the density of an ideal gas? pm + rt mrt + pv mrt ÷ pv pm ÷ rt