Environmental Science - Ch 2 Flashcards
Matter
Any material that has mass and occupies space (Solid, liquid, gas)
Chemistry
The study of the way matter interacts
Law of Conservation of Matter
Matter cannot be created nor destroyed. It can only be changed in form.
Element
A chemical substance with a set of properties that cannot be broken down into other substances with other properties
How many known elements exist?
118
Of those elements, how many of them are naturally occurring elements?
94
What are the five most common elements?
Hydrogen, Oxygen, Carbon, Silicon, Nitrogen
Atoms
Smallest units that maintain the chemical properties of the element
Protons
Positively charged particles
Electrons
Negatively charged particles
Neutrons
Particles with no charge
Atomic Number
The number of protons in the nucleus
What is Silicon’s atomic number?
14
Atomic Mass Number
The total number of protons and neutrons
Isotope
Atoms of the same element that have different numbers of neutrons. Will have a different atomic mass number.
Radioisotope
A heavy isotope that tends to be unstable before decomposing to a more stable isotope
Radioactivity
Process of spontaneous atomic decay
Molecule
Two or more like atoms combined chemically
Compound
Two or more different atoms combined chemically
Half Life
The amount of time it takes for 1/2 of a radioisotope to decay
Ions
Electrically charged atoms or combinations of atoms
Covalent Bond
When electrons are shared between atoms
What is this?
H
\
O-O
\
H
Hydrogen Peroxide
Ionic Bond
When electrons are shared unequally between atoms
Hydrogen Bond
Occurs when hydrogen is attracted to the negative end of a different molecule
Organic Compounds
Contain carbon and are mostly covalently bonded
Example of an Organic Compound
Glucose (C6H12O6)
Inorganic Compounds
Lack carbon and tend to be simpler
Example of an Inorganic Compound
Water (H2O)
What is the most abundant inorganic compound?
Water (H2O)
What elements do Carbohydrates and lipids contain?
Carbon, hydrogen, oxygen
Nucleic Acids
Direct the production of proteins
Deoxyribonucleic Acid (DNA) AND Ribonucleic Acid
Carry hereditary information for organisms and are responsible for passing traits from parents to offspring
Genes
Regions of DNA coding for particular proteins that perform particular functions
pH Scale
Measures how acidic or basic a solution is
What is the midpoint on the pH scale?
7
Energy
The capacity to change the position, composition, or temperature of matter
Work
When a force acts on an object, causing it to move
Potential Energy
Energy at rest
Kinetic Energy
Energy in motion
Thermodynamics
The study of the relationships between different forms of energy
First Law of Thermodynamics
Energy cannot be destroyed. It can only be changed in form
Second Law of Thermodynamics
Energy tends to change from a more ordered state to a less ordered state as it changes form
Autotrophs/Primary Producers
Use the sun’s radiation to produce their own food through photosynthesis
What is one example of an autotroph?
Algae, Plants, Certain Bacteria
Photosynthesis
Process where light energy is converted into chemical energy
Heterotrophs
Obtain energy by feeding on other organisms
Core
Earth’s center
Mantle
Surrounds the core, thick layer of less dense, elastic rock
Geology
The study of Earth’s physical features, processes, and history
Asthenosphere
Area of the upper mantle with especially soft rock
Lithosphere
Contains the uppermost mantle and crust
Crust
Thin, brittle, low - density layer of rock that covers the entire surface
Plate Tectonics
Movement by large plates in the lithosphere
How many plates does the Earth’s crust consist of?
15
Pangea
The continents were one large land mass that broke up
Divergent Plate Boundaries
Plates move apart as magma rises to the surface and cools
Transform Plate Boundaries
Plates slip and grind alongside each other
Subduction
Oceanic crust diving downward
Continental Collision
Mountain ranges form
Rock
Any solid aggregation of minerals
