Question

Hi
I have a biology question.

Answer 1

Post your question.

Answer 2

Why wouldn't the beryllium ion be neutral? I took a quiz and the question was marked as a stable but not a neutral ion. Thanks!

Answer 3

@aaronq

Answer 4

From what I understand an ion is neutral due to it having the same number of protons and electrons. Correct me if I am wrong.

Answer 5

Beryllium has an atomic number 4 and an atomic mass of 9. The beryllium ion is:

Answer 6

An element has the same number of protons and electrons.
An ion is actually defined as being electron deficient (a cation) or having an excess of electrons (an anion), making it electrically charged.

Beryllium will lose 2 electrons and become a cation, \(Be^{2+}\). This has to do with it's electron configuration because it's easier (in terms of energy) to ionize both of them, instead of gaining 6.

Answer 7

Ok. The last shell has 2 electrons in it so it will give them up instead of gaining six. What I am understand is that the first shell is stable because it has two but the second one isn't because it has 6. It would need 8 to be stable? Please tell me what makes an ion stable.

Answer 8

Each electron shell can hold a limited number of electrons. Although it is holding a limited number does that mean it can be unstable at the same time?

Answer 9

For an ion to be stable, it needs to have a e configuration like that of the Noble gases, (often referred to as an "octet"). The first few elements on the periodic table (along with transition metals) are an exception.

Hydrogen can gain 1 e, and become hydride \(H^{-}\)
Helium is stable on it's own (it's a Nobel gas).
Li will lose an electron, and become \(Li^+\).
Be will lose 2 electrons.

If you notice, they all have the same number of electrons as Helium does.

Answer 10

If an ion is electron deficient then it won't have the same number of protons? Would in ion be neutral if it doesn't have to give up it's electrons?

Answer 11

Sorry it has been a while since I have taken biology and I am taking it online. :)

Answer 12

The number of protons is always fixed for an element (it's what actually defines an element being that certain element, Oxygen will always have 8 protons if it doesn't it won't be oxygen).

The term "element" is used for the neutral form of a certain atom (same number of protons to electrons).
The term "ion" is actually used for an atom that does not have the same number of protons to electrons, because it has been "ionized" (a term for removing electrons), (It could have also gained electrons though, which in turn, it would have ionized another atom.)

Answer 13

It's okay, this is more chemistry related than biology.

Answer 14

Right..

Answer 15

Beryllium is stable because it gave up it's two electrons?

Answer 16

i'm gonna draw some lewis diagrams to illustrate the octet rule:


On the left Be will lose those two valence (outermost) electrons, on the right Magnesium will lose it's 2 valence electrons. Notice that they will both be 2+ cations, but the number of electrons in the shell before it differs, simply because of it's electron configuration and where it's situated (Mg is lower) on the periodic table.

Answer 17

Since it gave up it's two electron's , there are no longer an equal number of proton's and electron's within the atom, thus it won't be neutral?

Answer 18

yes, exactly. The type of neutrality were talking about here is electrical. Since electrons are negatively charged and protons positively (equal magnitude in charges), not having an equal number will result in a difference in charge.

Answer 19

This makes a lot more since. The octet rule means that each valence shell except for the first one, needs to have 8 electron's in it.

Answer 20

8 or more

Answer 21

The octet rule means that the atom will be stable when it has 8 electrons in it's valence shell. It can either lose electrons, or gain electrons, to achieve this configuration.

Answer 22

What a difference a tutor makes. I appreciate the help. Take care.

Answer 23

You're welcome. have a nice day