Drawing Bohr Ionic Compounds

Remember… An ion is a charged atom. This is caused by the loss or gain of electrons. A positive charge is caused by the loss of an electron. A negative charge is caused by the gain of an electron.

Same number of charges. The protons and electrons charges “cancel” each other out. The charge is +2 because two electrons were lost. The charge is -1 because one extra electron was gained. Protons do not change in number because they are stuck in the nucleus. The number of protons also defines what element the atom is.

Only the exterior shell of the atom can gain or lose electrons. We call these electrons valence electrons.

All the elements’ atoms on the left of the zig-zag line, (the metals), lose electrons / become positively charged. All the elements’ atoms on the right of the zig-zag line, (the non-metals), gain electrons / become negatively charged. Metalloids, around the zig-zag line, tend to have properties of both metals and non-metals. The way they lose or gain electrons still follows the rules above.

NON- METALS METALS ZIG-ZAG LINE

An ionic compound is composed of a metal ion and a non-metal ion via a chemical reaction. The metal ion gives one or more electrons to a non-metal ion. The now positive metal ion, (cation), and the now negative non-metal ion, (anion), are then stuck together due to their opposite charges. We call that an ionic bond.

A whole bunch of ions stuck together!!! Chlorine takes an electron. Sodium gives an electron. They are now stuck together!!! A crystal of table salt. A whole bunch of ions stuck together!!!

SOME EXAMPLES…

On the periodic table of elements, lithium gives one electron because it has a +1 charge. Chlorine takes one electron because it has a -1 charge. Both are satisfied, and the ionic compound is one to one. Li Cl

1 Draw the previous ionic compound like this, with the Bohr ions, brackets, and charges.

On the periodic table of elements, lithium gives one electron because it has a +1 charge. Oxygen takes two electrons because it has a -2 charge. So that both are satisfied, you need two ions of lithium so oxygen can get two electrons. The compound is one to two. Li O Li

x2 Draw the previous ionic compound like this, with the Bohr ions, brackets, and charges. Draw a “x2” to avoid having to actually draw two of them!

On the periodic table of elements, aluminum gives three electrons because it has a +3 charge. Nitrogen takes three electrons because it has a -3 charge. Both are satisfied, and the ionic compound is one to one. Al N

+3 Draw the previous ionic compound like this, with the Bohr ions, brackets, and charges.