warm up 4/2

Intro to Solutions

Solution – Homogenous mixture of 2 or more substancesSolvent – Substance that does the dissolving (there is more of this one)Solute – Substance that is dissolved

What solutes could be dissolved into this solvent?

Can these two solids dissolve into each other?

What is the solvent and what are the solutes?

Can a liquid be dissolved in a gas?

How do you know if something will dissolve

in something else?

Like Dissolves Like!• Polar dissolves in polar • Nonpolar dissolves in nonpolar• Nonpolar does not dissolve in polar

http://www.kentchemistry.com/links/bonding/LikeDissolveslike.htm

(polar means the molecule has a + & – end)

What Can Speed up the Solution Rate?

1. Agitation (stirring) – causes the molecules to collide more.

2. Greater surface area (crushing or grinding) – more solute for the solvent to act on.

3. Temperature – Kinetic energy (movement) causes molecules to collide more.

Water – Universal Solvent

You know that your body needs water,

but why?

Warm Up 4/15

But what makes water so special? Why isn’t a different liquid compound used in its place?

Why so Special?1.High Heat Capacity – prevents sudden

changes in body temp.2.Reactivity – it is a reactant in many of

the chemical reactions in our body (food digestion)

3.Solvent Properties – most reactions in the body don’t happen unless the reactions are dissolved in water.

When you’re ridin’ in a Chevy and you feel something heavy…

Electronegativity! O is more

electronegative than H, so the O atom gets the shared

electrons most of the time.

+

-

The water molecules pull the salt ions away.

http://www.kentchemistry.com/links/bonding/LikeDissolveslike.htm

Called Dissociation.

Hydrogen BondsThe polar ends of the water molecules attract the opposite ends of other water molecules.

Hydrogen Bond Activity

Question: How many drops of water do you think the surface of a penny can hold? Make a prediction on your paper.

Procedure: Use a pipette to drop water onto a penny to find out. Try to use a level surface.

Left Side – On Your Own

Create your own left side for this lesson that demonstrates that you understand the ideas we learned in your own creative way.