Chapter 2

Question 0

Steps of the scientific method

Answer 0

• problem
• research
• hypothesis
• experiment
• conclusion

Question 1

As problems arise, scientists must use the _______ ________to analyze the situation and formulate theories

Answer 1

Scientific method

Question 2

Sound science vs junk science.

Answer 2

Sound science: widely accepted by scientists who are considered experts in the field, subjected to peer review
Junk science: NOT SOUND

Question 3

What is a paradigm shift?

Answer 3

A major change is scientific theory.

Question 4

Law of conservation of matter

Answer 4

Substances may undergo a physical or chemical change. The element still exists, and is never thrown away. This creates pollutants-contaminants

Question 5

Pollutants are categorized based on their persistence. What are the four levels?

Answer 5

Degradable, biodegradable, slowly degradable, and non degradable.

Question 6

What does degradable mean?

Answer 6

Broken down completely to safe components.

Question 7

Define biodegradable.

Answer 7

Broken down with help of bacteria.

Ex, raw sewage.

Question 8

Define slowly degradable.

Answer 8

Takes decades or longer to break down. Ex, DDT, most plastics.

Question 9

Describe non degradable.

Answer 9

Can’t be broken down naturally. Ex, mercury, lead, and arsenic.

Question 10

Forms of nuclear change.

Answer 10

Radioactive decay, nuclear fission, Nuclear fusion

Question 11

Radioactive decay: what is it?

Answer 11

Radioactive isotopes change into a different isotope, emits radiation. Rate of decay expressed as a half life. Generally takes 10 half lubes for an element to reach a safe level of radiation.

Question 12

Plutonium 239, what’s its half life?

Answer 12

Half life of 24000

Question 13

What is nuclear fission

Answer 13

Nuclei split apart to smaller nuclei, releases neutrons and energy.
Form of nuclear changes used in nuclear reactors.

Question 14

Nuclear fusion, what is it?

Answer 14

Two isotopes are forced together under high temperature to form a heavier nucleus. Trying to develop as a new form of energy.

Question 15

First law of thermodynamics.

Answer 15

Energy cannot be created or destroyed.

Question 16

Second law of thermodynamics.

Answer 16

As energy is used high quality is transformed into usable low quality energy. Heat is transferred from hot to cold.

Question 17

What is thermodynamics.

Answer 17

It is an isolated system. This leads to an increase in entropy.

Question 18

The energy that is lost as you go up an energy pyramid is explained by____

Answer 18

The second law of thermodynamics.

Question 19

Earth is a closed system for ____ and an open system for _____

Answer 19

Matter, energy.

Question 20

Energy is

Answer 20

The ability to do work.

Question 21

Kinetic energy.

Answer 21

Uses light and other forms of radiation. Heat, motion, electrical power.

Question 22

Potential energy.

Answer 22

Reservoir behind hydroelectric damn, high pressure. Four types of chemical potential energy:battery, explosives, firewood, and gasoline.

Question 23

In the United States, what percentage of energy used is wasted?

Answer 23

84%. Only 16% of energy used actually performs work.

Question 24

What happens in single variable analysis. ****

Answer 24

Scientists set up 2 groups. One is an experimental group, in which the variable is changes in a known way the other is a control group in which the chosen variable is not changed.

Question 25

What happens in multivariable analysis.

Answer 25

Scientists run mathematical models on high speed computers to analyze the interactions of many variables without having to carry out traditional controlled experiments.

Question 26

Inductive reasoning.

Answer 26

Involves using specific observations and measurements to arrive at a her break conclusion or hypothesis. “Bottom up” reasoning.

Question 27

Deductive reasoning.

Answer 27

Involves using logic to arrive at a specific conclusion based on a generalization or premise
All birds have feathers. Eagles are birds. Eagles have feather.

Question 28

When does a feedback loop occur?

Answer 28

When an output of matter energy or information is fed back into the system as an input and leads to changes in that system

Question 29

Positive feedback loop causes…

Answer 29

A system to change further the same direction

Question 30

A negative feedback loop causes…

Answer 30

System to change in the opposite direction

Question 31

Time delays can allow a problem to build up slowly until it reaches a________

Answer 31

Threshold level/tipping point. This causes a fundamental shift in the behavior of a system.

Question 32

A synergistic interaction or synergy occurs when…

Answer 32

2 or more processes interact so that the combined effect is greater than the sum if their separate effects.

Question 33

Matter is

Answer 33

Anything that has mass and takes up space

Question 34

Elements

Answer 34

The distinctive building blocks of matter that make up every materials substance

Question 35

Compounds

Answer 35

Two or more different elements held together in fixed proportions by attractive forces called chemical bonds

Question 36

An atom

Answer 36

The smallest unit of matter that exhibits the characteristics of an element

Question 37

Subatomic particles

Answer 37

Positively charged protons, uncharged neutrons, and negatively charged electrons

Question 38

An ion

Answer 38

An Atom or groups of Atoms with one or more that positive or negative electrical charges

Question 39

A molecule

Answer 39

The combination of two or more Atoms of the same or different elements held together by chemical bonds

Question 40

Organic compounds

Answer 40

Contain at least two carbon atoms combined with each other and with atoms of one or more other elements

Question 41

Three factors determine the severity of the pollutants harmful effects

Answer 41

It’s chemical nature it’s concentration and it’s persistence

Question 42

What is persistence

Answer 42

A measure of how long the pollutants stays in the air water soil or body