UW OCEAN 421 - Properties of Water and Seawater (22 pages)

Previewing pages 1, 2, 21, 22 of 22 page document View the full content.
View Full Document

Properties of Water and Seawater



Previewing pages 1, 2, 21, 22 of actual document.

View the full content.
View Full Document
View Full Document

Properties of Water and Seawater

107 views


Pages:
22
School:
University of Washington
Course:
Ocean 421 - Special Topics in Physical Oceanography
Special Topics in Physical Oceanography Documents

Unformatted text preview:

Chpt 3 Properties of Water and Seawater 10 01 01 James W Murray Univ Washington I The Nature of pure water Seawater is mostly water H2O In fact it is about 96 5 wt water Sediments are also mostly water Most fine grained surface sediments have a porosity volume of pores to volume of solids of greater than 90 Almost every process we discuss will occur and be affected by water Thus water has been called the universal solvent Water has unique and unusual properties both in pure form and as a solvent These properties influence chemical reactions Structure of the water molecule The structure of H2O is shown in Fig 3 1 It consists of an O atom with 6 e that have the electronic configuration of 1 s2 2s2 2pz2 2py 2px which merge with two H atoms with 1 e each resulting in a neutral molecule with 8 e which form four pairs called sp3 hybrids The most stable configuration of these four lobes is a tetrahedral arrangement with two e in each lobe Two lobes are used for O H bonds shared electrons and two lobes have free lone pairs of electrons Fig 3 1 The water molecule lacks symmetry as for the linear O C O molecule e g CO2 that would otherwise cancel out polarity The H O H tetrahedral angle is 105 which is less than the ideal tetrahedral angle of 109 Fig 3 2 The reason this is so is because of e repulsion The bent structure explains why water has a dipole moment There is separation of charge which means it is a polar molecule An important aspect of the water molecule structure is its propensity to form hydrogen bonds H bonds H bonds often occur in liquids made up of molecules in which H is bonded to a highly electronegative element e g O N Cl or F 1 H bonds can be thought of as resulting from resonance of an H between two more polar atoms and necessitates that the three atoms be collinear e g see Fig 3 3 2 The H O H bond is relatively strong and has a strength of about 4 5 kcal mol 1 compared to 10 20 kcal mol 1 for ionic bonds and 0 5 kcal mol 1 for van der Waals bonds These H



View Full Document

Access the best Study Guides, Lecture Notes and Practice Exams

Loading Unlocking...
Login

Join to view Properties of Water and Seawater and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Properties of Water and Seawater and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?