Analyze each table of ionization energy data (in kJ/mol) to identify each element.

a. A Period 3 element (1 point)
IE1: 496, IE2: 4562, IE3: 6910, IE4: 9453, IE5: 13354, IE6: 16613, IE7:20117

b. A Period 5 element (1 point)
IE1: 403, IE2:2633, IE3: 3860, IE4:5080, IE5: 6850, IE6: 8140, IE7: 9570

c. A Period 2 element (1 point)
IE1: 1314, IE2: 3388, IE3: 5301, IE4: 7469, IE5: 10990, IE6: 13327, IE7: 71330

2 answers

I would go to the periodic table and just look up IE 1 through 7 for each period. For period 2 and 3 there aren't that many elements to check. Use this site.
http://www.webelements.com/chlorine/
or
webelements.com
thanks