Chlorine has seven electrons in its valence shell. It accepts an electron to complete its octet and becomes a chlorine ion (Cl-). What is the nature of this chlorine ion? A. Cation B. Anion C. Metal ion

Question

preetha · Answer

This is a Chemistry question. Please repost in Chem.

anonymous · Answer

You could post this in the Chemistry section, and someone there could probably give you a more detailed response. 

But I do think that I lot of biologists would know the answer to this question, too. 

First, let's use a process of elimination. 

C can't be the answer, because chlorine isn't a metal. It's a gas. You knew that right? 

So now, we're looking at A and B. 

Cations and Anions are two kinds of ions. 

What's an ion? An ion is an atom that DOES NOT have an equal number of protons and electrons.

CATIONS have LESS electrons than protons. That means that they're POSITIVELY charged. 

(Remember, electrons are negatively charged. So more electrons means negative charge.) 

ANIONS have MORE electrons than protons. So, they are NEGATIVELY charged. 

Now, Chlorine normally has 17 electrons and 17 protons. 

If it gets one more electron, then it will have 18 electrons, and 17 protons. 

What kind of ion would it be, then?

anonymous · Answer

is it anions?

anonymous · Answer

Yes! Anions. MORE electrons than protons.

anonymous · Answer

ty

anonymous · Answer

A simple "cute" way of remembering anions versus cations is that CATions (i.e. cats, the cute felines) as positive (as in good)...therefore, cations are ions with a positive charge.  And by default, anions have a negative charge.  In this problem, chlorine has a negative charge (more electrons than protons), therefore it is an anion