IONS

When you hear/see the word “ATOM” you can always assume that it is referring to the element in it’s

NEUTRAL state

A NEUTRAL ATOM means that there are the SAME number of positively charged PROTONS as there are

negatively charged ELECTRONS (the two charges balance out to zero)

Example: Nitrogen has +7 charge (protons)

and -7 charge (electrons) = 0 charge

REMINDER

Atoms can gain or lose electronsThis causes them to become electrically

charged

IONS = electrically charged atoms that have gained or lost electrons

IONS

Atoms will either lose some electrons or gain some electrons to become more stable

The most stable state for an atom is with a full octet (8 electrons in its valence shell)

The Noble Gases are all stable octets. Other atoms will gain or lose electrons to be stable like their nearest noble gas is

WHY DO IONS OCCUR?

Metal atoms lose e- to form positively charged cations

Example: Na loses 1 electron to become the ion Na +

CATIONS

Metal ions (cations) tend to lose electrons to become more stable

Example: Na atom has + 11 protons

And - 11 electrons

= 0 electric charge

But that one electron in it’s outer shell makes it unstable, so it will get rid of it and have the inner full shell its new

valence shell

Example:

Na ion has + 11 protons

And - 10 electrons

= +1 electric charge

METAL IONS

SODIUM ATOM VS. ION

Sodium ATOM (above) vs Sodium ION (above)

Notice that the ATOM has the SAME number p+ and e- Notice that the ION has 1 LESS electron than protons

Non-metal atoms gain e- to form negatively charged anions

Example: Cl picks up 1 electron to become the ion Cl-

ANIONS

Non-metal ions (anions) tend to gain electrons to become more stableExample:

Cl atom has + 17 protons And -17 electrons

= 0 electric charge

But that one electron missing in it’s outer shell makes it unstable, so it will pick up one to make its valence shell

fullExample:

Cl ion has + 17 protons And -18 electrons

= -1 electric charge

NON-METAL IONS

CHLORINE ATOM VS. ION

Chorine ATOM (above) vs Chlorine ION (above)

Notice that the ATOM has the SAME number p+ and e- Notice that the ION has 1 MORE electron than protons

HOW TO WRITE/SHOW AN ION

To write/show an ion, surround the element symbol with brackets, and write the new charge just outside the brackets in the top right

Metals lose electrons. Electrons are negatively charged. Each negative electron a metal atom loses makes it that much more

positively charged (it gets less negative).

Non-metals gain electrons. Electrons are negatively charged. Each negative electron a non-metal gains makes it that much more negatively charged (it gets more negative).

CHARGES

Don’t worry, we will go over some together… right now!

QUESTIONS?