ATC – 10th grade Science 1/10/2012

Water – The Universal Solvent The earth’s surface is about 70% water – the human body is about 65% water by mass. This is a clear indication that water is the most common substance on earth! It is important in dissolving many different substances even though everything is not soluble in water (for example, oil and water do not mix). The ability to dissolve so many substances makes us question why this is so. To understand, we need to look all the way down to the molecular unit of water.

Using what you have learned, answer the following questions: What makes up the water molecule? Do the three atoms that make up water share electrons equally? What is this distribution of electrons called?

Label the following diagram Labels to use: Negative end, Positive end, Hydrogen, Hydrogen, Oxygen, +, -

Turn in to your science teacher by Thursday, January 12