CHEM 210 Module 2- Water 2022/ 2023 (UPDATED) study guide

Module 2: Water 2.1:  Process of life take place in water-based environments  aqueous solutions  DNA, proteins, and carbohydrates are all produced in the aqueous- based cytoplasm  Interiors of organelles are water based with specialized proteins  Water is a unique molecule that contains only non-metal elements covalently bonded as H2)  Small non-metals can form stable covalent bonds due to significant overlap of atoms  Central oxygen atom forms two bonds with hydrogen  also has two sets of nonbonding electrons in valence shell  Total of 4 sets of electrons (2 sets bonding + 2 sets non-bonding) in the valence shell of oxygen, which we refer to as sp3 hybridization of the oxygen atom  Electron structure produces a bent molecular shape in water  Bent shape is the structural property of water  Bent shape combined with difference in electronegativity of oxygen and hydrogen atoms yields a polarized molecule  Difference of electronegativity with dipole arrows to indicate the direction of higher electron density  Dipole arrow points to the more electronegative atom, the oxygen in this case  Both hydrogen-oxygen bonds have arrows pointed toward oxygen  The combination of both of these dipole arrows results in the overall polarity for water  Entire molecule has an uneven distribution of electrons due to oxygen’s ability to attract electrons from both hydrogen atoms to it  Water is polar  Glucose is polar because of -OH functional groups and acetic acid (vinegar) due to carboxylic acid functional group  Cooking oil and bee’s wax are non-polar  Polar nature of water permits it to dissolve other polar molecules  Water can dissolve sugar be