Covalent Character
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Covalent Character
Hey y'all on the midterm 2 there was a question asking which element had the most covalent characters and I was just wondering what did that mean.
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Re: Covalent Character
Covalent character means that there is a low electronegativity difference between the elements. Where ionic character means there is high electronegativity difference.
For example: CH4 - is very covalent because C and H have almost the same electronegativity.
BaF2 - very ionic as Fluorine is the most electronegative on the periodic table and Barium has low electronegativity.
For example: CH4 - is very covalent because C and H have almost the same electronegativity.
BaF2 - very ionic as Fluorine is the most electronegative on the periodic table and Barium has low electronegativity.
Re: Covalent Character
Okay so something with MgS and MgO which would have the most covalent character ? Would the Charges come into play at all?
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Re: Covalent Character
MgS would have more covalent character than MgO because the electronegativity difference between MgS is smaller than between MgO.
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Re: Covalent Character
I went to Hannah Chew's Step Up session last Tuesday and she was really helpful in explaining covalent character. Basically, the smaller the cation, the greater covalent character and the larger the anion, the greater covalent character as well. I'll explain some of the few examples she had us do!
Between NaCl and KCl, which compound has greater covalent character? In this situation, we know that Na and K are both cations (they each have a charge of +1), so we know that we have to look at the size. Na+ is a smaller cation than K+ which means that it has more polarizing power and therefore, has more covalent character than K+.
Between NaCl and NaI, which compound has greater covalent character? In this situation, we know that Cl and I are both anions with a charge of -1, so we know that we have to compare the sizes once again. I- has a larger atomic radius than Cl-, which means that it has more polarizability and therefore, has more covalent character than Cl-.
This is another approach to deciding which compound has more covalent character, but another way to determine is by looking at electronegativity differences!
Between NaCl and KCl, which compound has greater covalent character? In this situation, we know that Na and K are both cations (they each have a charge of +1), so we know that we have to look at the size. Na+ is a smaller cation than K+ which means that it has more polarizing power and therefore, has more covalent character than K+.
Between NaCl and NaI, which compound has greater covalent character? In this situation, we know that Cl and I are both anions with a charge of -1, so we know that we have to compare the sizes once again. I- has a larger atomic radius than Cl-, which means that it has more polarizability and therefore, has more covalent character than Cl-.
This is another approach to deciding which compound has more covalent character, but another way to determine is by looking at electronegativity differences!
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Re: Covalent Character
To determine the extent of a molecules covalent character, we look at the atoms difference in electronegativities. If molecules have a very close electronegativity then they have a high covalent character. Difference in electronegativity<1.5= covalent.
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Re: Covalent Character
The one with the most covalent character would be the two molecules with the smallest electronegative values. The one with the smallest electronegativity difference is the answer.
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Re: Covalent Character
Molecules with more covalent character have a smaller electronegativity difference compared to molecules with ionic character. As a result of this smaller difference, there is no one atom which completely takes all the electrons, thereby making it more covalent. The important thing to consider when determining covalent character is polarizability. Let's say we are comparing hydrogen bonded to fluorine and hydrogen bonded to iodine. Iodine has a much greater polarizability, therefore making its electrons easily distorted. This allows more covalent character than the hydrogen bonded to fluorine because the fluorine pulls on the electrons much stronger.
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Re: Covalent Character
A more covalent ionic bond would have an electron cloud that is more shared. Either a cation with high polarizing power or anion with high polarizability (in the problem, usually either the cation or anion is constant across answer choices) will be more ionic. Hope this helps!
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Re: Covalent Character
I remember there was like a scale to determine covalent or ionic character where if the electronegativity difference is greater than 1.5 its more ionic and if less an 1.5 its more covalent.
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Re: Covalent Character
You simply look at the difference in electronegativity between the bonded elements. For example, a molecule with carbon and hydrogen is extremely covalent because they are very similar in electronegativity.
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Re: Covalent Character
Hi! Covalent character is how likely an atom is to share electrons with other atoms. There are trends of covalent character on the periodic table. As you move down a groups on the periodic table, the covalent character increases, and the covalent character decreases as you move left to right in periods. This is because as you move down a group and move left to right in a period, the electron number increases (meaning the electrons are further away from the nucleus).
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Re: Covalent Character
All ionically bonded compounds have some covalent character. The strength of the covalent character is different when looking at the cation or anion of the ionic compound. For cations, small, uncharged cations such as Al+3 have a greater covalent character as it can distort electrons to a greater degree. For anions, larger anions such as Br (compared to F) have a greater covalent character as it is easier to distort its electrons.
Re: Covalent Character
Ionic bonds involve significant differences between electronegativities. Therefore, molecules that display the most covalent character are those with the atoms with the least electronegativity.
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