The Properties of Water Earth’s Water Ch 1 Section 2

The “Universal Solvent” Water The “Universal Solvent”

Make a prediction… What do you think will happen when I pour hot, liquid wax into a glass of water? What did happen?

Water + Powder = When you make lemonade you are making a solution. Solution – a mixture that forms when one substance dissolves another. Solvent – the substance that does the dissolving (the water)

Water is called the “Universal Solvent” A solution is a mixture that forms when one substance dissolves another. The substance that does the dissolving is called the solvent, like water (because it is polar and attracts other substances).

Comparing Solvents With your group members, complete the Comparing Solvents activity on page 26. TIP: Do NOT let the measuring spoon touch the liquid (use the tooth picks to stir) Dispose of the liquids in cups A, B, and C in the sink. Leave D, E, and F on the countertop.

My Conclusions… In which solvent did each substance dissolve better? Each of the three substances dissolves better in water. 2. Propose an explanation for your results. Think about the differences between polar and nonpolar molecules. The substances must have had charged particles that were attracted to water’s polar molecules, but not to the nonpolar oil molecules.

Yeah water! Water dissolves so many substances that it is often called the “universal solvent”. Examples for states: Solid: cube of sugar added to tea, salt, and soap Liquids: bleach, rubbing alcohol Gases: oxygen and carbon dioxide (these dissolved gases are important for organisms that live in the water)

Nonpolar Some substances do not dissolve in water such as oils and wax. The molecules of oil are nonpolar molecules – they have no charged regions.