If there are originally 800 atoms of a radioactive isotope, how many would still be radioactive after 3 half-lives?

Complete the table for ion charge based upon their losing or gaining electrons in the outer shell. (use the periodic table as necessary.) group most likely ionic charge # of valence electrons i +1 ii +2 iii +3 iv +4 or -4 v -3 vi -2 vii -1 viii 0

200. ml of 3.00 m nacl solution is diluted to a final volume of 500. ml. what is the molarity of the final solution?

Place the elements below in order of decreasing ionization energy. aluminum(al) chlorine(cl) magnesium (mg) sulfur(s)