Periodic Trends

Moderators: Chem_Mod, Chem_Admin

Hannah Padilla 1H
Posts: 29
Joined: Fri Sep 28, 2018 12:19 am

Periodic Trends

Postby Hannah Padilla 1H » Thu Nov 08, 2018 10:05 am

I know that for Ionization energy, electronegativity, and electron affinity the trend is that it increases towards the upper right corner (He). However, how would you determine which atom is more electronegative if there are diagonal (like Na and Ca)

Kevin ODonnell 2B
Posts: 62
Joined: Fri Sep 28, 2018 12:24 am

Re: Periodic Trends

Postby Kevin ODonnell 2B » Thu Nov 08, 2018 10:28 am

A TA told me that going up a column (group) means it is more electronegative than just going across a row. So in this case Na would be more electronegative than Ca. I would still ask a TA for a further explanation on why this occurs though.

Posts: 83
Joined: Fri Sep 28, 2018 12:16 am

Re: Periodic Trends

Postby Kobe_Wright » Thu Nov 08, 2018 11:36 am

The above comment is wrong, Ca is actually more electronegative. Electronegativity increases as you go up a group and across a row because the farther up a group the less protons which means less pull to the nucleus and across the row means more valence electrons which increases the negative charge, but you need to check a chart of electronegativities to be sure for some elements.

Madelyn Romberg 1H
Posts: 102
Joined: Tue Oct 02, 2018 12:16 am

Re: Periodic Trends

Postby Madelyn Romberg 1H » Thu Nov 08, 2018 2:06 pm

When it comes to diagonal elements, it is generally difficult to [censored] their comparing electronegativity because you experience two opposing forces that influence electronegativity. In the case of sodium and calcium, sodium appears to have a higher electronegativity because it is in the period above calcium. However, calcium is also further into the period (a higher group) which increases the electronegativity. Therefore, with elements close together in a diagonal form, it is difficult to tell unless you are given their actual values.

Return to “Ionic & Covalent Bonds”

Who is online

Users browsing this forum: No registered users and 1 guest