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Chapter 2: Science, Matter, Energy, and Systems

2.1 What is science?

  • Science Is a Search for Order in Nature

    • Science: Understanding how nature functions and then using that understanding to forecast what is likely to occur in nature.

    • Scientific Process:

      • Identify a problem

      • Find out what is known about the problem (literature search)

      • Ask a question to be investigated

      • Perform an experiment to answer the question and collect data

      • Analyze data (check for patterns)

      • Propose a hypothesis to explain the data

      • Use the hypothesis to make testable predictions

      • Perform an experiment to test predictions

        • Accept hypothesis

        • Revise hypothesis

          • Make testable predictions

          • Test prediction

    • Scientific Hypothesis

      • A possible or testable explanation.

    • Experiment

      • Tests are done under controlled conditions and can be used to gather information and test ideas.

    • Model

      • An approximate representation or simulation of a system being studied.

    • Scientific Theory: A well-tested and widely accepted scientific hypothesis or a group of related hypotheses

    • Peer Review

      • Other scientists/people review the experiment and the data or repeat the experiment to see if the hypothesis is reasonable.

  • Important features of the scientific process

    • Curiosity

    • Skepticism

    • Peer review

    • Reproducibility •Openness to new ideas

  • Scientists Use Reasoning, Imagination, and Creativity to Learn How Nature Works

    • Inductive reasoning: Involves using specific observations and measurements to arrive at a general conclusion or hypothesis

      • Example: After dropping multiple objects from different heights we can conclude that objects will drop to the ground when we let them go.

    • Deductive reasoning: Using logic to get to a certain conclusion.

      • Example

        • Generalization or premise: all birds have feathers

          • Eagles are birds

        • Deductive conclusion: Eagles have feathers

  • Scientific Theories and Laws Are the Most Important Results of Science

    • Difference between Scientific Theory and Hypothesis

      • If many observations and studies support a hypothesis then it becomes a theory.

      • Theories must be supported by a multitude of tests and evidence from multiple scientists

      • A hypothesis is a tentative explanation that still requires more evidence to support it.

    • Scientific law or law of nature: A well-tested and widely accepted description of what we find happening over and over against in the same way in nature.

    • Paradigm shift: When new ideas overturn old ideas or theories.

  • The Results of Science Can Be Tentative, Reliable, or Unreliable

    • A fundamental part of science is testing

    • Tentative science or frontier science: Ideas that haven’t been peer-reviewed or widely tested and aren’t reliable.

    • Reliable science: Ideas that have data to support them and are accepted by scientists.

    • Unreliable science: Ideas that have not been tested widely or by others. It can also be ideas that have been tested but proven wrong so they are discarded.

  • Environmental Science Has Some Limitations

    • Scientists can disprove things but cannot prove things with 100% certainty

    • There can be bias in the experiments/tests

    • Things cannot be 100% accurately measured statistically. There is more estimation present.

    • There are many variables in the environment which can make experimenting with each thing expensive

    • The scientific process is only for natural-world questions but not ethical or moral questions.

    • Scientists cannot prove or disprove anything absolutely

    • Scientists are not free of bias about their own hypotheses and results

    • Systems in the natural world involve a huge number of variables and complex interactions

  • Tentative science, frontier science

    • Not yet considered reliable by the scientific community

  • Reliable science

    • Widely accepted by experts

  • Unreliable science

    • Has not been through peer review or has been discredited

2.2 What is Matter?

  • Matter consists of Elements and Compounds

    • Matter: Anything that has mass and takes up space

    • Elements: Each one of which is a fundamental material with a distinct set of qualities that cannot be chemically broken down into smaller chemicals.

    • Compounds: Combinations of two or more different elements held together in fixed proportions

  • Atoms, Ions, and Molecules Are the Building Blocks of Matter

    • Atom: The most basic building block of matter

    • Atomic theory: The idea that all elements are made up of atoms

    • Atomic number: Equal to the number of protons in the nucleus of its atom.

    • Mass number: The total number of neutrons and protons in its nucleus

    • Subatomic Particles:

      • Subatomic particles

        • The nucleus of the atom

          • Protons have a positive charge

            • Neutrons have a negative charge

        • Negatively charged electrons orbit the nucleus

    • Nucleus: Contains one or more protons and, in most cases, one or more neutrons

    • Isotopes: Forms of an element having the same atomic number but different mass numbers

    • Ion: Second building block of matter. Atoms or groups of atoms with one or more net positive or negative electrical charges

    • Acidity: A chemical property that influences how an object dissolved in water will interact with and change its surroundings.

    • pH: Measure of acidity

      • Below 7: Acidic solution

      • Exactly 7: Neutral solution

      • Above 7: Base solution

    • Molecule: A combination of two or more atoms of the same or different element held together by a chemical bond.

    • Chemical formula

      • Show the number of each type of atom or ion in a compound. (ex. NO3)

    • Important Elements

      • Hydrogen: H

      • Carbon: C

      • Oxygen: O

      • Nitrogen: N

      • Phosphorus: P

      • Sulfur: S

      • Chlorine: Cl

      • Fluorine: F

      • Bromine: Br

      • Sodium: Na

      • Calcium: Ca

      • Lead: Pb

      • Mercury: Hg

      • Arsenic: As

      • Uranium: U

    • Important Ions

      • Hydrogen ion: H+

      • Sodium ion: Na+

      • Calcium ion: Ca2+

      • Aluminum ion: Al3+

      • Ammonium ion: NH4+

      • Chloride ion: Cl-

      • Hydroxide ion: OH-

      • Nitrate ion: NO3-

      • Sulfate ion: SO4^2-

      • Phosphate ion: PO4^3-

    • Important Compounds

      • Sodium chloride: NaCl

      • Carbon monoxide: CO

      • Carbon dioxide: CO2

      • Nitric oxide: NO

      • Nitrogen dioxide: NO2

      • Nitrous oxide: N2O

      • Nitric acid: HNO3

      • Methane: CH4

      • Glucose: C6H12O6

      • Water: H2O

      • Hydrogen sulfide: H2S

      • Sulfur dioxide: SO2

      • Sulfuric acid: H2SO4

      • Ammonia: NH3

  • Organic Compounds are the Chemicals of Life

    • Organic compounds: Contain at least 2 carbon atoms and combine with atoms of one or more elements.

      • Types

        • Hydrocarbons and chlorinated hydrocarbons

        • Simple carbohydrates

      • Macromolecules: complex organic molecules

        • Complex carbohydrates, proteins, nucleic acids, and lipids

    • Inorganic compounds: Any other compounds that do not classify under an organic compound are put under this classification.

    • Macromolecules: Larger and more complex organic compounds are composed of this. Essential for life.

    • Polymers: Created when multiple monomers come together through chemical bonds.

    • Monomers: Simple organic molecules

    • Complex carbohydrates: Such as cellulose and starch, consist of two or more monomers of simple sugars such as glucose.

    • Proteins: Created by monomers called amino acids

    • Nucleic acids: Formed by monomers called nucleotides (DNA/RNA)

    • Lipids: Include fats and waxes, essential for life.

  • Matter Comes to Life through Genes, Chromosomes, and Cells

    • Cells and molecules are the fundamental structural units of life

    • Genes: Sequences of nucleotides in DNA molecules. They contain genetic information that allows us to create specific proteins

    • Trait: Each code of genetic information creates this and it’s a characteristic that’s given to the offspring by the parent.

    • Chromosome: Thousands of genes make one of these. Genetic information in this makes you unique and different from other species.

    • Relationship between genetic material to cells

      • A human body contains trillions of cells, each with an identical set of genes.

      • Each cell except for red blood cells contains a nucleus

      • Each has an identical set of chromosomes that are in pairs

      • A pair of chromosomes have one chromosome from each parent

      • Each chromosome contains a long DNA molecule In the form of a coiled double helix

      • Genes are segments of DNA on chromosomes that contain instructions to make proteins--the building blocks of life.

  • Matter Occurs in Various Physical Forms

    • Atoms, ions, and molecules have 3 physical states

      • Solid

        • Most compact and orderly arrangement

      • Liquid

        • Somewhere in between solids and gases

      • Gas

        • Has the least compact and orderly arrangement

  • Some Forms of Matter Are More Useful Than Others

    • Matter quality: The usefulness of a resource to us based on its availability and concentration

    • Concentration: Amount that is contained in a given area/volume

    • High-quality matter: High concentrations and is very available. High potential to be used as a resource

2.3 How can matter change?

  • Matter Undergoes Physical, Chemical, and Nuclear Changes

    • Physical changes: The arrangement of its atoms or ions does not change when change happens.

    • Chemical change/reaction: There is a change in the arrangement of atoms or ions within molecules of the substances involves.

    • Nuclear changes: Changes in the nuclei of its atoms.

    • Natural radioactive decay: Isotopes spontaneously emit fast-moving subatomic particles, high energy radiation such as gamma rays, or both.

    • Radioactive isotopes/radioisotopes: Unstable isotopes

    • Nuclear fission: When hit by neutrons, the heavy nuclei of some isotopes are broken up into lighter ones. Each process produces two or three neutrons as well as energy.

    • Nuclear fusion: Nuclear change in which two isotopes of light elements are forced together at high temperatures until they make a heavier nucleus.

  • We Cannot Create or Destroy Matter

    • Law of conservation of matter: No atoms are generated or destroyed during a physical or chemical change.

2.4 What is energy and how can it be changed?

  • Energy Comes in Many Forms

    • Energy: Is the capacity to transfer heat

    • Kinetic energy: Moving matter/energy

    • Heat: The total kinetic energy of all moving atoms, ions, or molecules within a given substance.

    • 3 methods of heat transportation

      • Radiation: The emission of electromagnetic energy

      • Conduction: The transfer of kinetic energy between substances in contact with one another.

      • Convection: The movement of heat within liquids and gases from warmer to cooler portions.

    • Electromagnetic radiation: Another form of kinetic energy. It travels in waves.

      • Radio waves, telewaves, etc.

    • Wavelength: Distance between successive peaks or troughs in the wave.

    • Potential energy: This is stored and potentially available for use.

  • Some Types of Energy Are More Useful Than Others

    • Energy quality: Measure of an energy source’s capacity to do useful work.

    • High-quality energy: Concentrated and has a high capacity to do useful work.

    • Low-quality energy: It disperses and has little capacity to do useful work.

  • Energy Changes Are Governed by Two Scientific Laws

    • Law of conservation of energy or The first law of thermodynamics: When energy is converted from one form to another in a physical or chemical change, no energy to created or destroyed

    • Energy consumption: Transferring energy across forms without causing any energy to be created or destroyed.

    • The second law of thermodynamics: We always end up with lower-quality or less useable energy than we did when energy transforms from one form to another.

    • Energy efficiency or energy productivity: This is a measurement of how much productive work is carried out by a specific energy input into a system.

2.5 What are systems and how do they respond to change?

  • Deforested areas turning to desert

    • Coral reefs dying

    • Glaciers melting

    • Sea levels rising

  • Systems Have Inputs, Flows, and Outputs

    • System: Set of components that function and interact in some regular way

    • Inputs: Come from the environment

    • Flows or throughputs: Matter and energy within the system of certain rates

    • Outputs: Goes to the environment

  • Systems Respond to Change through Feedback Loops

    • Feedback: Any process that increases (positive feedback) or decreases (negative feedback) a change to a system

    • Feedback loop: When a system's output of matter, energy, or information is sent back into it as an input, the system is changed.

    • Positive feedback loop: Causes a system to change further in the same direction

    • Negative or corrective feedback loop: Causes a system to change in the opposite direction from which is it moving

  • Time Delays Can Allow a System to Reach a Tipping Pointe

    • Time delays: Complex systems often show time delays between the input of a feedback stimulus and the response to it.

    • Threshold level or tipping point: Time delays can also allow an environmental problem to build slowly until it reaches a tipping point.

  • System Effects Can Be Amplified through Synergy

    • Synergistic interaction or synergy: This happens when two or more processes work together to produce an effect that is bigger than the sum of the effects of each process acting alone

Chapter 2: Science, Matter, Energy, and Systems

2.1 What is science?

  • Science Is a Search for Order in Nature

    • Science: Understanding how nature functions and then using that understanding to forecast what is likely to occur in nature.

    • Scientific Process:

      • Identify a problem

      • Find out what is known about the problem (literature search)

      • Ask a question to be investigated

      • Perform an experiment to answer the question and collect data

      • Analyze data (check for patterns)

      • Propose a hypothesis to explain the data

      • Use the hypothesis to make testable predictions

      • Perform an experiment to test predictions

        • Accept hypothesis

        • Revise hypothesis

          • Make testable predictions

          • Test prediction

    • Scientific Hypothesis

      • A possible or testable explanation.

    • Experiment

      • Tests are done under controlled conditions and can be used to gather information and test ideas.

    • Model

      • An approximate representation or simulation of a system being studied.

    • Scientific Theory: A well-tested and widely accepted scientific hypothesis or a group of related hypotheses

    • Peer Review

      • Other scientists/people review the experiment and the data or repeat the experiment to see if the hypothesis is reasonable.

  • Important features of the scientific process

    • Curiosity

    • Skepticism

    • Peer review

    • Reproducibility •Openness to new ideas

  • Scientists Use Reasoning, Imagination, and Creativity to Learn How Nature Works

    • Inductive reasoning: Involves using specific observations and measurements to arrive at a general conclusion or hypothesis

      • Example: After dropping multiple objects from different heights we can conclude that objects will drop to the ground when we let them go.

    • Deductive reasoning: Using logic to get to a certain conclusion.

      • Example

        • Generalization or premise: all birds have feathers

          • Eagles are birds

        • Deductive conclusion: Eagles have feathers

  • Scientific Theories and Laws Are the Most Important Results of Science

    • Difference between Scientific Theory and Hypothesis

      • If many observations and studies support a hypothesis then it becomes a theory.

      • Theories must be supported by a multitude of tests and evidence from multiple scientists

      • A hypothesis is a tentative explanation that still requires more evidence to support it.

    • Scientific law or law of nature: A well-tested and widely accepted description of what we find happening over and over against in the same way in nature.

    • Paradigm shift: When new ideas overturn old ideas or theories.

  • The Results of Science Can Be Tentative, Reliable, or Unreliable

    • A fundamental part of science is testing

    • Tentative science or frontier science: Ideas that haven’t been peer-reviewed or widely tested and aren’t reliable.

    • Reliable science: Ideas that have data to support them and are accepted by scientists.

    • Unreliable science: Ideas that have not been tested widely or by others. It can also be ideas that have been tested but proven wrong so they are discarded.

  • Environmental Science Has Some Limitations

    • Scientists can disprove things but cannot prove things with 100% certainty

    • There can be bias in the experiments/tests

    • Things cannot be 100% accurately measured statistically. There is more estimation present.

    • There are many variables in the environment which can make experimenting with each thing expensive

    • The scientific process is only for natural-world questions but not ethical or moral questions.

    • Scientists cannot prove or disprove anything absolutely

    • Scientists are not free of bias about their own hypotheses and results

    • Systems in the natural world involve a huge number of variables and complex interactions

  • Tentative science, frontier science

    • Not yet considered reliable by the scientific community

  • Reliable science

    • Widely accepted by experts

  • Unreliable science

    • Has not been through peer review or has been discredited

2.2 What is Matter?

  • Matter consists of Elements and Compounds

    • Matter: Anything that has mass and takes up space

    • Elements: Each one of which is a fundamental material with a distinct set of qualities that cannot be chemically broken down into smaller chemicals.

    • Compounds: Combinations of two or more different elements held together in fixed proportions

  • Atoms, Ions, and Molecules Are the Building Blocks of Matter

    • Atom: The most basic building block of matter

    • Atomic theory: The idea that all elements are made up of atoms

    • Atomic number: Equal to the number of protons in the nucleus of its atom.

    • Mass number: The total number of neutrons and protons in its nucleus

    • Subatomic Particles:

      • Subatomic particles

        • The nucleus of the atom

          • Protons have a positive charge

            • Neutrons have a negative charge

        • Negatively charged electrons orbit the nucleus

    • Nucleus: Contains one or more protons and, in most cases, one or more neutrons

    • Isotopes: Forms of an element having the same atomic number but different mass numbers

    • Ion: Second building block of matter. Atoms or groups of atoms with one or more net positive or negative electrical charges

    • Acidity: A chemical property that influences how an object dissolved in water will interact with and change its surroundings.

    • pH: Measure of acidity

      • Below 7: Acidic solution

      • Exactly 7: Neutral solution

      • Above 7: Base solution

    • Molecule: A combination of two or more atoms of the same or different element held together by a chemical bond.

    • Chemical formula

      • Show the number of each type of atom or ion in a compound. (ex. NO3)

    • Important Elements

      • Hydrogen: H

      • Carbon: C

      • Oxygen: O

      • Nitrogen: N

      • Phosphorus: P

      • Sulfur: S

      • Chlorine: Cl

      • Fluorine: F

      • Bromine: Br

      • Sodium: Na

      • Calcium: Ca

      • Lead: Pb

      • Mercury: Hg

      • Arsenic: As

      • Uranium: U

    • Important Ions

      • Hydrogen ion: H+

      • Sodium ion: Na+

      • Calcium ion: Ca2+

      • Aluminum ion: Al3+

      • Ammonium ion: NH4+

      • Chloride ion: Cl-

      • Hydroxide ion: OH-

      • Nitrate ion: NO3-

      • Sulfate ion: SO4^2-

      • Phosphate ion: PO4^3-

    • Important Compounds

      • Sodium chloride: NaCl

      • Carbon monoxide: CO

      • Carbon dioxide: CO2

      • Nitric oxide: NO

      • Nitrogen dioxide: NO2

      • Nitrous oxide: N2O

      • Nitric acid: HNO3

      • Methane: CH4

      • Glucose: C6H12O6

      • Water: H2O

      • Hydrogen sulfide: H2S

      • Sulfur dioxide: SO2

      • Sulfuric acid: H2SO4

      • Ammonia: NH3

  • Organic Compounds are the Chemicals of Life

    • Organic compounds: Contain at least 2 carbon atoms and combine with atoms of one or more elements.

      • Types

        • Hydrocarbons and chlorinated hydrocarbons

        • Simple carbohydrates

      • Macromolecules: complex organic molecules

        • Complex carbohydrates, proteins, nucleic acids, and lipids

    • Inorganic compounds: Any other compounds that do not classify under an organic compound are put under this classification.

    • Macromolecules: Larger and more complex organic compounds are composed of this. Essential for life.

    • Polymers: Created when multiple monomers come together through chemical bonds.

    • Monomers: Simple organic molecules

    • Complex carbohydrates: Such as cellulose and starch, consist of two or more monomers of simple sugars such as glucose.

    • Proteins: Created by monomers called amino acids

    • Nucleic acids: Formed by monomers called nucleotides (DNA/RNA)

    • Lipids: Include fats and waxes, essential for life.

  • Matter Comes to Life through Genes, Chromosomes, and Cells

    • Cells and molecules are the fundamental structural units of life

    • Genes: Sequences of nucleotides in DNA molecules. They contain genetic information that allows us to create specific proteins

    • Trait: Each code of genetic information creates this and it’s a characteristic that’s given to the offspring by the parent.

    • Chromosome: Thousands of genes make one of these. Genetic information in this makes you unique and different from other species.

    • Relationship between genetic material to cells

      • A human body contains trillions of cells, each with an identical set of genes.

      • Each cell except for red blood cells contains a nucleus

      • Each has an identical set of chromosomes that are in pairs

      • A pair of chromosomes have one chromosome from each parent

      • Each chromosome contains a long DNA molecule In the form of a coiled double helix

      • Genes are segments of DNA on chromosomes that contain instructions to make proteins--the building blocks of life.

  • Matter Occurs in Various Physical Forms

    • Atoms, ions, and molecules have 3 physical states

      • Solid

        • Most compact and orderly arrangement

      • Liquid

        • Somewhere in between solids and gases

      • Gas

        • Has the least compact and orderly arrangement

  • Some Forms of Matter Are More Useful Than Others

    • Matter quality: The usefulness of a resource to us based on its availability and concentration

    • Concentration: Amount that is contained in a given area/volume

    • High-quality matter: High concentrations and is very available. High potential to be used as a resource

2.3 How can matter change?

  • Matter Undergoes Physical, Chemical, and Nuclear Changes

    • Physical changes: The arrangement of its atoms or ions does not change when change happens.

    • Chemical change/reaction: There is a change in the arrangement of atoms or ions within molecules of the substances involves.

    • Nuclear changes: Changes in the nuclei of its atoms.

    • Natural radioactive decay: Isotopes spontaneously emit fast-moving subatomic particles, high energy radiation such as gamma rays, or both.

    • Radioactive isotopes/radioisotopes: Unstable isotopes

    • Nuclear fission: When hit by neutrons, the heavy nuclei of some isotopes are broken up into lighter ones. Each process produces two or three neutrons as well as energy.

    • Nuclear fusion: Nuclear change in which two isotopes of light elements are forced together at high temperatures until they make a heavier nucleus.

  • We Cannot Create or Destroy Matter

    • Law of conservation of matter: No atoms are generated or destroyed during a physical or chemical change.

2.4 What is energy and how can it be changed?

  • Energy Comes in Many Forms

    • Energy: Is the capacity to transfer heat

    • Kinetic energy: Moving matter/energy

    • Heat: The total kinetic energy of all moving atoms, ions, or molecules within a given substance.

    • 3 methods of heat transportation

      • Radiation: The emission of electromagnetic energy

      • Conduction: The transfer of kinetic energy between substances in contact with one another.

      • Convection: The movement of heat within liquids and gases from warmer to cooler portions.

    • Electromagnetic radiation: Another form of kinetic energy. It travels in waves.

      • Radio waves, telewaves, etc.

    • Wavelength: Distance between successive peaks or troughs in the wave.

    • Potential energy: This is stored and potentially available for use.

  • Some Types of Energy Are More Useful Than Others

    • Energy quality: Measure of an energy source’s capacity to do useful work.

    • High-quality energy: Concentrated and has a high capacity to do useful work.

    • Low-quality energy: It disperses and has little capacity to do useful work.

  • Energy Changes Are Governed by Two Scientific Laws

    • Law of conservation of energy or The first law of thermodynamics: When energy is converted from one form to another in a physical or chemical change, no energy to created or destroyed

    • Energy consumption: Transferring energy across forms without causing any energy to be created or destroyed.

    • The second law of thermodynamics: We always end up with lower-quality or less useable energy than we did when energy transforms from one form to another.

    • Energy efficiency or energy productivity: This is a measurement of how much productive work is carried out by a specific energy input into a system.

2.5 What are systems and how do they respond to change?

  • Deforested areas turning to desert

    • Coral reefs dying

    • Glaciers melting

    • Sea levels rising

  • Systems Have Inputs, Flows, and Outputs

    • System: Set of components that function and interact in some regular way

    • Inputs: Come from the environment

    • Flows or throughputs: Matter and energy within the system of certain rates

    • Outputs: Goes to the environment

  • Systems Respond to Change through Feedback Loops

    • Feedback: Any process that increases (positive feedback) or decreases (negative feedback) a change to a system

    • Feedback loop: When a system's output of matter, energy, or information is sent back into it as an input, the system is changed.

    • Positive feedback loop: Causes a system to change further in the same direction

    • Negative or corrective feedback loop: Causes a system to change in the opposite direction from which is it moving

  • Time Delays Can Allow a System to Reach a Tipping Pointe

    • Time delays: Complex systems often show time delays between the input of a feedback stimulus and the response to it.

    • Threshold level or tipping point: Time delays can also allow an environmental problem to build slowly until it reaches a tipping point.

  • System Effects Can Be Amplified through Synergy

    • Synergistic interaction or synergy: This happens when two or more processes work together to produce an effect that is bigger than the sum of the effects of each process acting alone

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