Presentation on theme: "Water: My Favorite Molecule Ronald R. Martin Department of Chemistry University of Western Ontario."— Presentation transcript:
Water: My Favorite Molecule Ronald R. Martin Department of Chemistry University of Western Ontario
Lets Meet Two Elements Introducing Hydrogen (H) The lightest element But 70% of the mass of the known universe.
Hydrogen In Space
Lets Meet Two Elements Introducing Hydrogen (H) The lightest element But 70% of the mass of the known universe. And Oxygen (O) or as it occurs in our Atmosphere O 2 About 20 % of the air we breathe is oxygen
Atoms and Molecules Put atoms together and you get molecules, some very big, some very small
Molecules can be very small, such as H 2 (2 amu); or they can be huge, like proteins (> 10,000 amu) The protein cytochrome c consists of thousands of atoms, all linked by covalent bonds. Its mass is 12,360 amu
Putting Hydrogen and Oxygen Together Yields Water
HOH or H 2 O
DensityDensity and phasephase 1000 kg·m 3, liquid (4 °C) 917 kg·m 3, solid Melting point0 °C, 32 °F ( K) °C°FK  Boiling point100 °C, 212 °F ( K)   Physical Properties of Water
Whats So Amazing About Water Lots, but most important to us: You Cant Have Life Without IT! About 70% of the Human Body is Water
Water in Outer Space
Water is a Major Component of Comets
Water Has been Found on the Moon,Moon on the planets Mercury, Mars, and Neptune,MercuryMarsNeptune on the dwarf planet Pluto,Pluto on satellites of planets, such as Triton and Europa.TritonEuropa The liquid form of water is only known to occur on Earth strong evidence suggests that it is present just under the surface of Saturn's moon Enceladus.SaturnEnceladus
Earth From Space It looks as if theres lots of water The bad news, there isnt !
Some Facts About Water On Earth Most of it is too salty to drink, or to be used for agriculture Much of the fresh water is frozen as ice
Much of Our Water is Frozen
Some Facts About Water On Earth Most of it is too salty to drink, or to be used for agriculture Much of the fresh water is frozen as ice Some countries have a lot
Some Facts About Water On Earth Most of it is too salty to drink, or to be used for agriculture Much of the fresh water is frozen as ice Some countries have a lot Some have very little, in fact 18 countries now have insufficient water for their needs, the economic and social consequences are immense.
Waterless Northern India
Lets talk about Australia 80 % of all its agriculture is sustained by the Murray-Darling watershed.
The Problem With The Murray- Darling Average peak flow per month: 2,000,000,000,000 liters Peak flow 2006 per month: 250,000,000,000 Peak flow 2007 per month: 100,000,000,000 Flow is now 1/20 peak average.
What The Darling Looks Like Today
Reasons? Australia grows both cotton and rice at the sources of the Murray and the Darling Downstream demand increases as populations grow Control is fragmented, divided between the state and federal governments and is hopelessly out of date But there is a much bigger and more important reason!
SO We know there is limited useful water on the surface of the earth. We know water use is increasing exponentially. We know we are changing the climate of the planet in ways that will adversely affect water supply and distribution. Its one of our most important molecules. Its time to start doing something to protect the resource.