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Thank God We are Worth More than the Sum of our Parts!!. Insufficient Iodine and Goiters. Maybe We Should Call it "Almost". ATOMS: Organized Collection of Protons, Neutrons, and Electrons. Helium. Carbon. Naturally Occurring Isotopes. Radioactive Isotopes. Why Electrons "Matter".
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ATOMS: Organized Collection of Protons, Neutrons, and Electrons Helium
Why Electrons "Matter" 3rd Shell 2nd Shell 1st Shell
Van der Waal's Forces: Why Geckos Can Run Up the Wall
The Wonders of Water Why water? Water is involved in and is a common product of many biological reactions. H O H Water provides an environment in which many biological reactions take place. H O H
Water is Polar H2O Water is held together by covalent bonds, but oxygen keeps the electrons around it more than the hydrogens do. The result...oxygen has a slight negative charge while hydrogen has a slight positive charge.
Water is polar. Show how polarity leads to hydrogen bonding between 8 different water molecules. - - Hydrogen bond O H H + + Water molecule - - - - - - - - O O - - O O H H H H O H - - H + + + + + + H H H H O + + + + H H + + - - - - - - - - O O O O H H H H + + + + H H H H + + + +
Liquid Water Ice
1 Cells are made of 70-95% water. In addition, cells are surrounded by water. As a result _____. A the temperature of living things changes relatively slowly B a variety of nutrients are available as dissolved solutes C waste products can be easily removed D dissolved substances can be easily transported within cells or between cells in multicellular organisms E all of the above
2 Water is polar. This means that _____. A the opposite ends of the water molecule have opposite electrical charges B water molecules are linear. C water is just one of the many hydrophobic molecules D all of the atoms in a water molecule have equal electronegativities E all of the above
3 The partial positive and partial negative charges on a water molecule occur because of _____. A the unequal sharing of electrons between the oxygen and the hydrogen atoms in a water molecule B the stability of one atom of a bond but not the other atom C covalent bonding D ionic bonding E hydrogen's high electronegativity
4 In a drop of water molecules, hydrogen bonds form between _____. A two oxygen atoms in different water molecules B the hydrogen atoms in two different water molecules C the hydrogen atom in one water molecule and a oxygen atom in another water molecule D the hydrogens in a single water molecule E none of the above
5 You fill a glass of water to just slightly above the rim without it spilling over the glass. What property of water best explains this? A surface tension B adhesion C its thermal properties D ice is less dense than water E none of the above
6 Because molecules of water are farther apart in ice than in liquid form, _____. A ice floats B ice is denser than liquid water C ice expands when it melts D ice vaporizes before liquid water does E all of the above
7 Nonpolar molecules that do not interact with water molecules are called _____. A covalent B hydrophillic C hydrophobic D none of the above