Use a sheet of notebook paper to do your daily warm up. You will turn them in every few weeks!

175kg = _____ g

What 2 parts make up the nucleus of an atom?

What does the atomic number of an element indicate?

What 2 things in an atom must be equal for the atom to be considered neutral?

Why is Earth called the Blue Planet?It’s covered mostly by water!

Water is the most abundant compound in most living things!

The human body is about 60-70% water!

In order to understand life on Earth, we need to understand some of the basic properties of water!

Properties of Water

A Molecule of Water

Written as H2O

CohesionAttraction of water molecules to each other

They stick together!

Water can form multiple hydrogen bonds between molecules!

AdhesionAttraction of water molecules to other things

They stick to other things!

This is why a meniscus forms (water molecules stick to the side of the graduated cylinder)!

Are the above pictures showing an example of adhesion or cohesion?A. AdhesionB. Cohesion

Adhesion & Cohesion

Adhesion & Cohesion also make it possible for water to travel from the roots to the top of a plant!

Polarity of WaterAlthough water is electrically neutral, it does exhibit polarity!

This means that a water molecule has 1 slightly negative end & 1 slightly positive end!

The electrons in a water molecule crowd around the oxygen atom, giving it a negative charge & the hydrogen atoms become more positive.

Polarity & Solubility

Solubility refers to the ability of a substance (solute) to dissolve in another substance (solvent)

In a water/sugar solution, water is the solvent & sugar is the solute!

This is what happens when oil & water get together. Is oil polar or nonpolar?

PolarNonpolarNot enough info

Nonpolar!

If we know water & oil don’t mix & that water is POLAR, oil must be NONPOLAR!

Some people add sugar to their coffee. Is sugar polar or nonpolar? VB CGBDFBDFBDFBDBBBBVBBBBB Polar Nonpolar Not enough info.

Polar!

We know sugar will dissolve in water, so sugar must be polar, just like water.

Is coffee polar or nonpolar?

Polar!

Now we know that sugar is polar & that it will dissolve in coffee, so coffee must be polar!

Mixtures2 or more substances in same place, but not chemically combined

Substances in a mixture keep their individual properties!

Solutions

The dissolved material (solute) becomes evenly distributed through the entire liquid (solvent)

Suspensions

Mixture of water & a non-dissolved material

Mud is a suspension, because the dirt is not fully dissolved in the water!

Trick question! It’s a solution & a suspension! Blood is mostly water, but many substances are dissolved in it. However, the cells in blood remain in suspension!