1. Science, Matter, Energy and Systems
Miller and Spoolman, Ch 2

2. Pre-Assessment Probes
What do you remember from prior classes and your summer assignment?
Read through and respond to the three scenarios dealing with matter and systems.
Include your responses on the PowerPoint (no names)
Find the slide with your answer choice as the heading
Give your reasoning in the content space below

4. Seedlings in a Jar

5. A. The total mass of the original jar with seeds will be more than the total mass of the jar with the seedlings.
The plants grow, generating more cells and therefore more mass.
because the plants now exist and produce oxygen

6. B. The total mass of the original jar with seeds will be less than the total mass of the jar with the seedlings.
as these seedlings develop and grow roots, their mass will increase as the mass of the moist-to-dry towel decreases.

7. C. There will be no change in the total mass of the jar with seedlings after 12 days.
due to the conservation of energy
you can't make something out of nothing, so the mass stays the same.
law of conservation of mass, jar is a closed system
The system is closed, so the mass should stay the same because nothing is entering or leaving the jar (Mass cannot be created or destroyed).

8. C. There will be no change in the total mass of the jar with seedlings after 12 days.
The law of conservation of mass states that matter is neither created or destroyed in any chance or reaction.
Because mass cannot be created or dsetroyed

9. Chicken Eggs

10. Group A: We think an egg will gain mass
Group A: We think an egg will gain mass. An egg’s mass is more just before hatching than when the egg was laid.
after the egg is laid, it continues to grow and develop, gaining in size and mass.
because it is growing
as the chick develops organs and body parts, its mass will increase.

11. Group B: We think an egg will lose mass
Group B: We think an egg will lose mass. An egg’s mass is less just before hatching than when the egg was laid.
the mass of the water/moisture in the fertilized egg will be lost

12. Group C: We think the mass of an egg stays the same as the chick develops inside.
due to the conversation of energy and mass  the chicken takes nutrients from the egg
the chick will eat the yolk of the egg and the nutrients will become a part of the chick, so there is no mass gained or lost.
The egg is a closed system, mass cannot be created or destryed and nothing is entering or leaving the system.

13. Group C: We think the mass of an egg stays the same as the chick develops inside.
The egg, incubator combo is a closed system, and within a closed system, mass cannot be created or destoyed
no matter can be created or destroyed so the system has 500 grams at the beginning and end
Since no mass can be created or destroyed, the mass will stay the same

14. Is It a System?

15. Things that are systems
Systems: everything except density= mass over volume, a box of nails and a graph
Everything but the box of nails
Aquarium, earth, grasshopper, volcano, ocean, digestion, food web, hurricane, seed, bicycle, earth and moon, cell phone, electrical circuit, water cycle, human body.

16. What is a system?
any set of parts working together to form a complex whole
a group of components that work together to form one thing.
If different componenets of the thing needed to work together to operate, then we determined that it was a system

17. What is science?
Scientists collect data and develop theories, models, and laws about how nature works.

18. Science is a search for order in nature
Science is about working to understand how the natural world works and use that knowledge to make predictions about what is likely to happen in the future
Conducted in a systematic manner: the scientific method/process
Key features include curiosity, skepticism, peer review, reproducibility, and openness to new ideas.

20. Scientists use reasoning, imagination, and creativity
Inductive reasoning
Use specific observations and measurements to come to a conclusion
You see examples and apply to all
“Bottom up”  specific to general
Deductive reasoning
Logic based
You know of ideas and apply to specifics
“Top down”  general to specific.

21. Scientific theories and laws are the most important results of science
Science theory vs. public theory
Theory vs. law
Theory: explanation of observations
Law: observations
Paradigm shift.

22. The results of science can be tentative, reliable or unreliable
Check your source! (Think Wikipedia, media news, etc.)
Tentative  frontier science; new stuff
Reliable  lots of widely accepted data
Unreliable  has not been subjected to peer review, or unsupported by peer review.

23. Environmental science has some limitations
Scientists can disprove things, but they cannot prove anything absolutely (use “prove” with caution…or better yet, not at all)
Scientists are human
The world is a big place
Many variables and complex interactions
The scientific process only applies to the natural world, not ethics or morality.

24. What Is Matter?
Matter consists of elements and compounds which are in turn made up of atoms, ions, or molecules

25. Matter consists of elements and compounds
Matter: stuff (aka anything that takes up space and has mass)
Elements: fundamental substance, cannot be broken down into anything simpler (ex. H and O)
Compounds: Combinations of two or more elements in fixed proportions (ex. H2O)

26. Atoms, ions, and molecules are the building blocks of matter
Atom: a single “piece” of an element
Protons, neutrons, electrons
Nucleus: protons & neutrons

27. Atoms, ions, and molecules are the building blocks of matter

28. Atoms, ions, and molecules are the building blocks of matter
Isotopes: elements with the same atomic number but different mass
Aka different number of neutrons
Ion: elements with the same atomic number, but with a charge
aka different number of electrons
Why ions??!!?!?!?! WHY!??!?!?!?!?!?
Different ions are essential for plant growth (ex. Nitrates)
pH balance is critical for living organisms in both water and soil.

29. Atoms, ions, and molecules are the building blocks of matter
Molecule: Combination of two or more atoms of the same or different elements held together by chemical bonds
Chemical formula: shows the number of each type of atom or ion in a compound.

30. Organic Compounds are the Chemicals of Life
Organic compounds: compounds that contain at least two carbon atoms, and at least one hydrogen atom
Ex. Carbohydrates, proteins, lipids, nucleic acids, etc.
Inorganic compounds: everything else
Ex. CO2, O2, H2O, salts, etc.

31. Matter Comes to Life through Genes, Chromosomes and Cells

32. Matter Occurs in Various Physical Forms
Matter can be found in one of three physical states: solid, liquid, or gas
Depends on the spacing and orderliness of the of the molecules.

33. How Can Matter Change?
When matter undergoes a physical or chemical change, no atoms are created or destroyed (the law of conservation of matter)

34. Matter Undergoes Physical, Chemical and Nuclear Changes
Physical change: a change in which the arrangement of atoms or ions does not change
Ex. Ice melting into liquid water
Chemical change (aka chemical reaction): A change in the arrangement of atoms or ions
Ex. Burning a piece of paper.

35. Matter Undergoes Physical, Chemical and Nuclear Changes
Nuclear changes: change occurs in the nucleus of an atom
Natural radioactive decay: isotopes spontaneously emit sub-atomic particles
Nuclear fission: splitting apart of massive nuclei (ex. Uranium-235)
Nuclear fusion: two isotopes of smaller size or forced together until they fuse (only happens at EXTREMELY high temperatures).

36. We Cannot Create or Destroy Matter
Atoms can only be rearranged through reactions and changes, never destroyed or created
Law of conservation of matter: when a physical or chemical change occurs, no atoms are created or destroyed
Everything we think we have thrown away remains here with us in some form.

37. What Is Energy and How Can It Be Changed?
When energy is converted from one form to another in a physical or chemical change, no energy is created or destroyed (first law of thermodynamics.
Whenever energy is changes from one form to another, we end up with lower-quality and less usable energy than we started with (second law of thermodynamics).

38. Energy Comes in Many Forms
Energy: capacity to do work or transfer heat
Kinetic energy: Movement
Ex. Wind, flowing water, electricity
Heat
Radiation, conduction, convection
Electromagnetic radiation
Gamma rays, X rays, UV rays, etc.
Potential energy: Stored energy
Ex. Piece of coal.

39. Some Types of Energy Are More Useful Than Others
Energy quality is a measure of an energy source’s capacity to do useful work
High quality vs. low quality.

40. Energy Changes Are Governed by Two Scientific Laws
Law of conservation of energy (aka first law of thermodynamics)
When energy is converted from one form to another in a physical or chemical change, no energy is created or destroyed
Energy input = energy output
Second Law of thermodynamics
When energy changes from one form to another, we always end up with lower-quality or less usable energy than we started with
Second form of energy is usually heat.

41. What Are Systems and How Do They Respond to Change?
Systems have inputs, flows and outputs of matter and energy, and their behavior can be affected by feedback.
Life, human systems and the earth’s life-support systems must conform to the law of conservation of matter and the two laws of thermodynamics.

42. Systems have inputs, flows, and outputs
System: set of components that function and interact in some regular way
Ex. Human body, river, etc.

43. Systems respond to change through feedback loops
Feedback: any process that increases (positive feedback) or decreases (negative feedback) a change to a system
Positive: Pressure on the opening of the uterus results in increased contractions during childbirth
Negative: Sweating when your body temperature gets too high
Feedback loops occur when an output of matter, energy or information is fed back into the system as input.

44. System effects can be amplified through synergy
Synergy occurs when two or more processes interact so that the combined effect is greater than the sum of their separate effects
“The whole is greater than the sum of its parts.”
Ex. Smoking, asbestos and lung cancer

45. Human activities can have unintended harmful effects
Everything that we do affects someone or something in the environment in some way
Complex systems  unpredictable
Ex. Clearing the Amazon rain forest for agricultural use.