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Intro to Chemistry: Ionic Bonds, Covalent Bonds, and Radioactivity Unit 7 Notes – Part C. How do atoms make ionic bonds ?. Remember this? - Elements combine with each other to form compounds. H. O. O. O. H. H. O. H. H. How do atoms become stuck together? And why?. H.
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Intro to Chemistry:Ionic Bonds, Covalent Bonds, and RadioactivityUnit 7 Notes – Part C
Remember this?- Elements combine with each other to form compounds. H O O O H H O H H How do atoms become stuck together? And why? H
Atoms “want” 8 valence electrons! The octet rule:atoms react (bond to gain/lose electrons) to achieve 8 valence electrons (Exception: H and He only “want” 2). Sometimes this even means getting rid of all of their valence electrons!
Ionic Bonds… are like stealing Ionic bond: a transfer of electrons from one atom to another. Why do you think this bond is called ionic?
Yesterday we said that atoms sometimes steal from one another to achieve 8 electrons…but is there another way??
Covalent bonds“sharing” Covalent bond = when two atoms share valence electrons to achieve full valence shells.
Sharing always occurs in pairs of electrons.A line between two atoms represents a covalent bond of 2 electrons. H How many valence electrons does a hydrogen bring? How many valence electrons does a carbon bring? H C H H Does every atom have a full valence shell?
How to draw covalent compounds: 1. Find total number of valence electrons in the compound 2. Connect all the atoms with covalent bonds 3. Fill in empty spots with remaining valence electrons (so that each atom has a full shell) 4. Check to make sure you used the right number of valence electrons
Examples: H2O H2S