Covalent Bonding

Covalent Bonding

Ionic Bonding Remember that in an ionic bond, electrons are __________ between atoms. transferred This transfer creates _____; both ___ and ___; that are _________ to each other. ions + _ attracted This attraction holds the ________ together. compound

_ + The ionic bond is the __________between the positive K+ ionand the negative F- ion attraction K F

H Covalent Bonding Instead of transferring electrons, what if we ______ them? share Look at hydrogen… It has ____ valence electron – needs ___ more to complete its valence shell. one one

H H Covalent Bonding Let’s add another hydrogen… Each hydrogen needs one more electron – what would happen if they ________ the one they already have? shared

H H Covalent Bonding Now -- _____ hydrogens have ____ valence shells! both full one By sharing ____ pair of electrons, both atoms are _____! full

Cl The other side…? What about the other side of the table? Cl has ___ valence electrons – only needs ___ more to fill its valence shell. 7 one Could we do the same thing with 2 Cl’s?

Cl Cl Cl Cl The other side…? These atoms are _______ one pair of e- sharing *Each _____ of shared electrons is one _________ bond. pair covalent

Who goes there? Covalent bonds are formed between a ________ and another _________. nonmetal nonmetal Electrons are _______ instead of __________. shared transferred

You drew it wrong! If you noticed – I drew the dot diagram differently than I taught you… I didn’t make a mistake – it’s just easier to think of these like ‘puzzle pieces’. If you match up the unpaired electrons, it’s easier to draw circles around the octets…

Predictions… Is there a way to ______ how many covalent bonds an element will form? predict Look at the number of ________ electrons you start with. valence Then figure out how many ______ are needed to ________ your valence shell. more complete That’s the number of _______ that element will form! bonds

Predictions… All elements in group ___ need ____ more valence electron, so they will form ____ covalent bond. 17 one one Group ___ elements have ___, need ___, so they form ___ covalent bonds. 16 6 2 2 Group ___ elements have ___, need ___, so they form ___ covalent bonds. 15 5 3 3

What’s the difference? How do you know if a formula is a covalent or ionic compound? Look at the ______ of atoms that make up the compound! types Ionic = _______ + __________ metal nonmetal Covalent = _________ + _________ nonmetal nonmetal

What am I? CaCl2 ionic NO2 covalent NH3 covalent MgBr2 ionic

What’s My Name? Remember that for ionic compounds, the ______ comes first, then the _________ -- which ends in ______. metal nonmetal “-ide” Since covalent compounds are made of two ___________, how do you come up with the name? nonmetals

What’s My Name? All covalent compounds have ____ names – one for the ______ element and one for the _______. two first second What we have to do is add a _______ to tell us how ______ atoms of each element are ________ in the compound. prefix many present

Rules for Naming 1. Write the _____ of the first element. name more than 1 2. If there is __________ of the first element – add the appropriate _______. prefix 3. The second element _________ gets a prefix! ALWAYS second 4. Change the end of the ________ name to ______. “-ide”

Examples CO2 Carbon dioxide N2O3 Dinitrogen trioxide H2O Dihydrogen monoxide

Covalent Bonding