WATER
UNDERGROUND WATER
Porosity: measure of how much of a rock is open space. This space
can be between grains or within cracks of a rock
Permeability: measure of the ease with which a fluid can move
through a porous rock.
POROSITY AND PERMEABILITY LAB
Question: What is the porosity and permeability of
different soils and rocks?
Hypothesis: If soil, sand, and pebbles are used, then
_________ will have the greatest porosity.
Hypothesis: If soil, sand, and pebbles are used, then
_________ will have the greatest permeability.
Observations:
Conclusion:
MINI POROSITY LAB
Sandstone
Limestone
Basalt
Find dry mass, soak overnight, find wet mass. Which stone would serve as a better
aquifer?
WATER
Water: H2O molecule
Hyrdogen Bond: weak attraction between
H (+ charge) and O (-charge)
Water molecules have one negative
charge and two positive charges (opposite
charges attract)
STATES OF WATER
Molecules are always moving, Changing
from one state to another, heat is either
lost or gained
Gas: molecules are separate, lots of heat
so moving fast
Liquid: molecules form weak attraction
(hydrogen bond), move more slowly
Solid: hydrogen bonding holds together in
6 sided lattice pattern, least heat energy,
move slowly
Heat travels from areas of high temp to low temp
 ex: you are holding ice, heat travels form hand to ice
Evaporation: molecules if liquid water move quickly breaking bonds becoming water
vapor. Heat is ABSORBED.
 EX: Water in pan on stove. Heat from pan goes to water, water molecules heat up and become gas
molecules.
Condensation: air molecules slow down, weak bonds are made. Heat is RELEASED.
 EX: Water Vapor near mirror, heat leaves water and goes to mirror. Air molecules cool down and
become liquid water.
Freezing:
Melting:
DURING FREEZING TEMPERATURES, WHY WOULD
THEY SPRAY DOWN ORANGE TREES WITH WATER?
PROPERTIES OF WATER
1. More things dissolve (become incorporated into a liquid) in water than in any other
substance.
 Compounds that also have positive or negative charges form hydrogen bonds with water.
 Nutrients in soil dissolve in water and are taken up through plants roots.
2. When water freezes, the molecules form a lattice pattern
 Cold water molecules move close together. During freezing, instead of moving very close together, a
lattice structure (ice) forms. Solid water molecules are farther away then liquid water molecules.
Therefore, ice is less dense than liquid causing ice to float.
 If ice were denser, then ponds and lake would freeze from the bottom up and plant life would be
affected.
DENSITY
Density: heating and cooling affects the
density of water.
Heating water speeds up the movement
causing the molecules to move farther
apart. This is why warmer water is less
dense than colder water.
As water cools, molecules lose heat and
move more slowly moving closer together
making cold water denser.
Ice is less dense due to its lattice structure,
so it floats.
ADHESION AND COHESION
Cohesion: attraction between water molecules
between each other
 Surface Tension: result of cohesions, water molecules
attracted to each other but not the gas molecules above
the water surface water. Water surface to behave like a
stretched membrane
Adhesion: attraction of water molecules to other
substances, like soil or glass
 Capillary action: water adheres to other substances, water
molecules can travel this way. EX: Water moving up a
paper towel
WATER CYCLE
Evaporation: liquid to a vapor, may evaporate from the ocean, river,
lake or glacier
Condensation: when water vapor cools, clouds form when water vapor
condenses into water droplets or ice crystals
Precipitation: water falls from the sky as rain, snow, sleet, or hail. High
up in the atmosphere, precipitation usually stars as snow and melts into
rain.
Runoff: precipitation that reaches the ground and flows on the surface
Infiltration: percolates into the soil becoming groundwater
Transpiration: evaporation of water from pores (stomata) on the
surface of plants’ leaves. Helps plants transport water upward from
their roots through their tissues. Cohesive and adhesive properties of
water all contribute to water circulation through a plant.
Evapotranspiration: combined effects of evaporation and transpiration
WATERSHED
Watershed: Area that drains water to a low point: river
stream, arroyo, lake, etc.
Majority of Arizona’s land is contained within the Colorado
River Watershed, which mean that water that falls on most of
the water as rain or snow as the potential to find its way
through tributaries and groundwater movement to the
Colorado River.
GROUNDWATER: READING 1
WHAT, WHERE, HOW AND WHY
Unsaturated Zone
Saturated Zone
Aquifer
Discharge
Direction Water Flows
Artesian Well/Aquifer
Spring
Water Table
Recharge