# Electronegativity Confusion

• MichaelXY
In summary, electronegativity is not about the positive charge of a species, but rather its ability to attract electrons. It is found across covalent bonds and is influenced by the number of electronic orbitals and the proton number. In the context of a neuron's membrane potential, the movement of K+ ions through a potassium channel results in a net potential of -70 mv due to the unequal distribution of +1 ions on either side of the membrane.

#### MichaelXY

[SOLVED] Electronegativity Confusion

## Homework Statement

Looking at the periodic chart and going down, the electronegativity goes down, ie Na = .9 and K = .8 From the definition electronegativity is the ability to attract electrons. So is that to say the more electronegative would actually be the more positively charged? I ask because I am getting confused with the K pump in a neuron cell. It seems as though the side that has more Na ions is more positive than the membrane side with K ions.

Thanks

## The Attempt at a Solution

electronegativity is not about how much positively charged a species is. It has to do with how much shielding there is on the nucleus of the species. Electronegativity is found across covalent bonds. It is the tendency with which an atom attracts a shared pair of electron towards itself.

The greater the number of electronic orbitals and the lesser the proton number, the lesser the electronegativity of the species.

So let me ask. If you had a Sodium atom on one side of a membrane, and a potassium on the other side, and were some how able to place a meter across each membrane, which side would read more positive? I am still trying to relate this to the membrane potential of a neuron.

Thanks

i've not yet done membrane potential for neurones... but from a physics point of view, and i am assuming you are talking about sodium and potassium ions, both species have the same charge, i.e +1 or both have a proton more than electrons. the sodium ion and the potassium ion have the same charge.

Ok, I think I got my answer. On one side of the membrane are K+ ions, the other side is Na+ ions. A potassium channel allows K+ ions to move freely between the membranes, until equillibrium of K+, so one side has more +1 ions than the other side, resulting in a net potential of -70 mv.

## 1. What is electronegativity?

Electronegativity is a measure of an atom's ability to attract electrons towards itself in a covalent bond.

## 2. How is electronegativity determined?

Electronegativity is determined by the number of protons in an atom's nucleus and the distance between the nucleus and the valence electrons.

## 3. What is the difference between electronegativity and electron affinity?

Electronegativity is a measure of an atom's ability to attract electrons in a covalent bond, while electron affinity is the energy released when an atom gains an electron in a chemical reaction.

## 4. Why do some elements have multiple electronegativity values?

Some elements have multiple electronegativity values because electronegativity can vary depending on the specific chemical bond or compound in which the element is involved.

## 5. How does electronegativity affect the properties of a molecule?

Electronegativity helps to determine the polarity of a molecule, which affects its physical and chemical properties such as melting point, boiling point, and solubility.