4 posts • Page 1 of 1
Covalent bonds that have an increasing difference in electronegativity have increasing ionic character. Therefore, a larger radius means decreasing electronegativity, which means less difference in electronegativity between the 2 atoms, which means less ionic character.
Ionic character is relative to another atom, so not all small atoms may have ionic character. Like O2 is a fairly small atom (according to the trends), but because it's bonded with another O (that has the same electronegativity) then it's covalent because they are sharing equally. Same with if you had two large atoms sharing. So I wouldn't look at size necessarily for determining ionic and covalent character, and if you do that really is only used to compare electronegativities because it's the greater difference in electronegativities between two atoms that call for a more ionic character.
Ionic character is the difference in electronegativity. The greater the difference, larger the ionic character is and conversely smaller the difference larger the covalent character is. So for example if we are comparing CO2 and CS2 carbon's electronegativity is 2.5, oxygen is 3, and sulfur is approximately 2.8. Because the difference between 3 and 2.5 is greater than the difference between 2.8 and 2.5 CO2 has a greater ionic character.
Who is online
Users browsing this forum: No registered users and 1 guest