Water & Solutions

Water’s Special Properties!#1- Ice Floats

• When water freezes, its structure locks air pockets in. • This makes water less dense as a

solid than as a liquid.Question: How would our Earth be

different if it didn’t float?

Special Property #2

• Water absorbs and retains heat.

–How does this affect living organisms?–HINT: What is your body temp?

Special Property #3

• Water molecules stick to each other. (Cohesion)

-Water can stay a liquid at room temp. because it sticks together!

Special Property #4

• Water molecules stick to other polar substances. (Adhesion)

• Fig. 5 on p. 55–The water is moving up the stem of

the plant.

Key Terms:• Cohesion- The attraction of particles of the

same substance.• Adhesion- The attraction of particles of

different substances.• Solution- A mixture, in which 2 or more

parts are evenly dissolved. (Has a solute & solvent.)– Solute- This part dissolves.– Solvent- This part does the dissolving.

Key Terms cont.• Acid-Substances that give off H+ ions in

water.• Bases-Substances that give off OH- ions in

water.• pH- The measure of how acidic or basic a

substance is.• Buffer- Prevents pH changes in a

substance. Look at p. 57