Science, Matter, Energy, and Systems (Chapter 3) Flashcards
Science
Endeavor to discover how nature works and to use that knowledge to make predictions about what is likely to happen in nature
Data
Information need to answer a question
Experiments
Porcedures carried out under controlled conditions to gather information and test ideas
Scientific Hypothesis
Possible and testable explanation of what they observe in nature or in the results of their experiments
Model
Approximate representation or stimulation of a system being studied
Scientific Theory
Well-tested and widely accepted scientific hypothesis or a group of related hypotheses
Peer Review
Scientists report details of the methods and models they used, the results of their experiments, and the reasoning behind their hypotheses for other scientists working in the same field to examine and criticize
Inductive Reasoning
Use of specific observations and measurements to arrive at a general conclusion or hypothesis; a form of “bottom-up” reasoning that goes from the specific to the general
Deductive Reasoning
Use of logic to arrive at a specific conclusion based on a generalization or premise; a form of “top-down” reasoning that goes from the general to the specific
Scientific Law
Well-tested and widely accepted description of what we find happening over and over again in the same way in nature
Paradigm Shift
New discovery or new idea overthrows a well-accepted scientific theory or law
Frontier Science
Preliminary results that have not yet been widely tested and accepted by peer review
Reliable Science
Data, hypotheses, theories and laws that are widely accepted by scientists who are considered experts in the field under study
Limitations of Environmental Science
Scientists can disprove things but they cannot prove anything absolutely; Scientists are human and are not totally free of bias; Statistical sampling; Large number of complex variables
Matter
Anything that has mass and takes up space
Elements
Fundamental substance that has a unique set of properties and cannot be broken down into simpler substances by chemical means
Compounds
Combinations of two or more different elements held togther in fixed proportions
Atom
Smallest unit of matter into which an element can be divided and still retain its chemical properties
Atomic Theory
Idea that all elememts are made up of atoms
Symbol for Hydrogen
H
Symbol for Carbon
C
Symbol for Oxygen
O
Symbol for Nitrogen
N
Symbol for Phosphorus
P
Symbol for Sulfur
S
Symbol for Chlorine
Cl
Symbol for Fluorine
F
Symbol for Bromine
Br
Symbol for Sodium
Na
Symbol for Calcium
Ca
Symbol for Lead
Pb
Symbol for Mercury
Hg
Symbol for Arsenic
As
Symbol for Uranium
U
Subatomic Particles
Protons (p), Neutrons (n) Electrons (e)
Nucleus
Small and dense center of an atom that contains one or more protons and usually one or more neutrons
Atomic Number
Equal to the number of protons in the nucleus
Mass Number
Mass of an atom; total number of protons and neutrons
Isotope
Forms of an element having the same atomic number but different mass number
Ion
Atom or group of atoms with one more net positive or negative electrical charges
Acidity
Chemical characteristic that determines how a substance dissolved in water will interact with and affect its environment
pH
Measure of acidity based on the amount of hydrogen ions (H+) and hydroxide ions (OH-) contained in a volume of a solution
Acidic Solution
Solution with more hydrogen ions than hydroxide ions and has a pH of less than 7
Basic Solution
Solution with more hydroxide ions than hydrogen ions and has a pH greater than 7
Molecule
Combination of two or more atoms of the same or different elements held together by forces called chemical bonds
Chemical Formula
Shows number and type of atom or ion in a compound
Organic Compound
Compounds that contain at least two carbon atoms combined with atoms of one or more other elements
Hydrocarbon
Organic compound of carbon and hydrogen atoms; examples include methane (CH4) and octane (C8H18)
Chlorinated Hydrocarbon
Compounds of carbon, hydrogen, and chlorine atoms; example is the insecticide DDT (C14H9Cl5)
Simple Carbohydrates
Compounds of carbon, hydrogen, and oxygen; example is glucose (C6H12O6)
Complex Carbohydrates
Consist of two or more monomers of simple sugars
Proteins
Formed by monomers called amino acids
Nucleic Acids
Compound formed by monomers called nucleotides
Cell
Fundamental structural unit of life
Genes
Sequence of nucleotides within DNA molecules
Trait
Characteristic passed on from parents to offspring during reproduction in an animal or plant
Chromosome
Special DNA molecule made of thousands of genes
Physical Change
Matter changes state (solid, liquid, gas) but does not change in chemical composition
Chemical Change
Change in the arrangement of atoms or ions within molecules
Nuclear Change
Change to the nuclei of an atom; includes natural radioactive decay, nuclear fission, and nuclear fusion
Law of Conservation of Matter
States that when a physical or chemical change occors, no atoms are created or destroyed
Energy
Capacity to do work or transfer heat
Kinetic Energy
Energy that comes from mass and velocity
Heat
Form of kinetic energy due to moving atoms, ions and molecules
Methods of Heat Transfer
Radiation, Conduction, Convection
Electromagnetic Radiation
Form of kinetic energy which travels in the form of a wave as a result of changes in electric and magnetic fields
Potential Energy
Energy which is stored and potentially available for use
Energy Quality
Measure of energy source’s capacity to do work
Law of Conservation of Energy or 1st Law of Thermodynamics
No energy is created or destroyed when it is converted from one fore to another in a physical or chemical change
2nd Law of Thermodynamics
When energy changes from one form to another, we alsway end up with lower-quality or less usable energy
Energy Efficiency
Measure of how much useful work is accomplished by a particular input of energy into a system
Feedback or Feedback Loop
Process that increases or decreases a change to a system
Positive Feedback Loop
Process that causes a system to change further in the same direction
Negative Feedback Loop
Process that causes a system to change in the opposite direction
Tipping Point
Threshold level in a system that causes a fundamental shift in the behavior of a system
