Lecture 1 Wednesday,February1,204:10PM Bonds: • Hydrogenbond: an electron-deficient hydrogenofone water is attractedto the unshared electrons ofwater forminga hydrogen bond ○ Has electrostatic(opposite charges)andcovalent (electron sharing) characteristics • 4 hydrogen bonds formedby 1 water molecule ○ Hydrogenbonds are the weakest bonds- theycan easilybe broken(why water isfluid- keepsformingandbreaking hydrogen bonds over time) ○ Covalent bonds are strong- connect oxygen and hydrogen ○ Hydrogenbonds are betweentwo water molecules ○ Semi-ionicinnaturebe notclassified asionicbonds because ionicbonds giveand takeelectrons -this isnot presenthere ○ A bond issimplysomethingthat interacts • Waterisanidealbiologicalsolvent ○ Salt ismade up ofionic bonds ○ Hydrogenbonds are betweentwo water molecules ○ Semi-ionicinnaturebe notclassified asionicbonds because ionicbonds giveand takeelectrons -this isnot presenthere ○ A bond issimplysomethingthat interacts • Waterisanidealbiologicalsolvent ○ Salt ismade up ofionic bonds § Ionic bonds are stronger than hydrogen bonds ○ Salt can easilydissolve inwater ○ Hydrogenbonds are brokenwhen youadd something to water (allowsthe salt to dissolve) • Waterhasa high meltingandboilingpoint ○ Water'smeltingandboilingpoints areexceptionallyhighdue tohydrogenbonding § Each water molecule can form four hydrogen bon
