Review of Ionic Bonding
Do this: Draw a picture of sodium just with its symbol as the nucleus and the electrons, in appropriate energy levels, around it.
Do this: Draw a picture of chlorine just with its symbol as the nucleus and the electrons, in appropriate energy levels, around it.
Question What does sodium want to do? Why?
Question What does chlorine want to do? Why?
Question How many protons does sodium have? How many electrons does it now have? What is its overall electrical charge?
Question How many protons does chlorine have? How many electrons does it now have? What is its overall electrical charge?
The positive sodium ion and the negative chloride ion are “electrostatically attracted” to one another. That’s an ionic bond. Occurs between a metal and nonmetal.
Covalent Bonding
Covalent Bonding Information It only happens between nonmetals Instead of gaining or losing electrons, atoms become stable by sharing electrons 2 shared valence electrons form 1 covalent bond These shared electrons are represented by a single line in diagrams
Covalent Bonding Remember the Octet Rule: atoms tend to gain, lose or share electrons so they have eight electrons in their outermost energy level. THEY BECOME STABLE!!
Covalent Bonding Here’s an example: Draw a picture of oxygen. Show the nucleus with the right number of protons and show only the right number of valence electrons.
Now draw 2 pictures of hydrogen Now draw 2 pictures of hydrogen. Again, show the nucleus and the valence electrons.
Covalent Bonding Now, combine these 2 diagrams and make sure each atom has a filled outer energy level.
Water!
Water!! Now draw the water molecule replacing the shared electrons with lines
Water!!
Electron Dot Diagrams Now try this: Draw a picture of every atom in the row that begins with lithium (Li) For the nucleus, just use the element’s symbol. For the electrons, only use the valence electrons
Electron Dot Diagrams
Electron Dot Diagrams
Electron Dot Diagrams Now, let’s draw them another way Writes the symbol of lithium. Draw a dot for every valence electrons lithium has next to the symbol Draw the dots (electrons) around the symbol, one per right, top, left and bottom, until you run out of electrons