CHEMISTRY (A STORY OF TWO SUBSTANCES)
experiment
A research method in which an investigator manipulates one or more factors to observe the effect on some behavior or mental process
Scientific Method
A series of steps followed to solve problems including collecting data, formulating a hypothesis, testing the hypothesis, and stating conclusions.
scientific law
A statement that describes what scientists expect to happen every time under a particular set of conditions
Conclusion
A summary based on evidence or facts
Hypothesis
A testable prediction, often implied by a theory
why do scientists use mass to measure instead of weight?
Weight is a force rather than a measure of the amount of matter something contains.
What are chlorofluorocarbons?
a family of chemical compounds containing chlorine, fluorine, and carbon
(Scientific)Theory
a well-tested concept that explains a wide range of observations
substance
also known as a chemical, is matter that has a definite and uniform composition
systematic approach
an organized method of solving a problem
What is carbon tetrachloride
invisible gas
Trophosphere
layer of Earth's amosphere closest to Earth's surface (where weather takes place and where most pollution occurs), contains the air we breathe, where airplanes fly,
applied research
scientific study that aims to solve practical problems
UVB
ultraviolet light B , increased levels of ultraviolet radiation
independent variable
variable that is manipulated from group to group
dependent variable
what is being measured
How does ozone form?
when ultraviolet rays from the sun act on oxygen in the upper atmosphere
synthetic
(adj.) made or put together by people; (n.) something artificial
Ozone
A form of oxygen that has three oxygen atoms in each molecule instead of the usual two. made up of oxygen, substance in the atmosphere that absorbs most harmful radiation before it reaches earths surface
Steps of the ozone being formed (3)
1. O^2 gets exposed to the sun/rays 2. molecules of O^2 are made of 2 smaller oxygen particles 3. energy of the radiation breaks O^2 into individual oxygen particles (O) and interact with O^2 to form O^3
Layers of the atmosphere
1. Troposphere: contains air we breathe 2. Stratosphere: the ozone layer is located in this layer 3. Mesosphere: where weather and temperature occurs 4. Thermosphere: contains nitrogen and oxygen
1. mass 2. weight 3. model
1. a coherent, typically large body of matter with no definite shape2. the force exerted on the mass of a body by a gravitational field3. 3D representations of a person or thing of a proposed structure
identify six substances mentioned in the book that are important in everyday life and are made of chemicals.
1. fertilizers 2. pesticides3. building materials4. beauty products5. plastics6. high-tech fabrics
Explain a chemical model by completing the following sentences.The 1._________, composition, and 2.___________ of all matter can be explained on a 3._________ level. All that we observe depends on 4._________ and the 5.________ they undergo. 6.________ seeks to explain the submicroscopic events that lead to 6.________________. One way to do this is by making a chemical mode, a 7.____________ of a 8.___________.
1. structure2. behavior3. submicroscopic4. atoms5. changes6. macroscopic observations7. 3-D representation8. submicroscopic event
model
A pattern, plan, representation, or description designed to show the structure or workings of an object, system, or concept
Matter
Anything that has mass and takes up space
How do chlorofluorocarbons affect the ozone layer?
Break down, causing holes and destroying it's protective qualities.
How does ozone form?
By being exposed to ultraviolet radiation in the upper regions of the stratosphere
Scientists detected thin areas in the ozone layer over Antartica. What could be causing the ozone hole?
CFCs were first detected in the atmosphere in the 1970s and the concentrations continued to increase through the 1990's, this could take oxygen away from ozone.
CFCs
Chlorinated Fluorocarbons are chemicals that break down the ozone layer
How is ozone measured?
Dobson units
Where does ozone form?
Equator where the rays of the sun are the strongest and then flows towards the poles
control group
In an experiment, the group that is not exposed to the treatment; contrasts with the experimental group and serves as a comparison for evaluating the effect of the treatment.
qualitative data
Information describing color, odor, shape, or some other physical characteristic
O^2
Oxygen
Analyze the importance of chemistry in our society using the branches of chemistry as examples.
The branches of chemistry can apply different aspects of chemistry to our society, such as advances in medicine.
why are there different branches of chemistry?
The branches of chemistry overlap those of physics and biology.
independent variable
The experimental factor that is manipulated; the variable whose effect is being studied.
dependent variable
The outcome factor; the variable that may change in response to manipulations of the independent variable.
Do tomatoes grow fastest under fluorescent, incandescent, or natural light? (dependent varaible)
The rate of growth of the tomato plant
Stratosphere
The second-lowest layer of Earth's atmosphere; the ozone layer is located in the upper stratosphere. ozone layer protects earth and located in stratosphere
Bio chemistry
The study of processes that take place in organisms
Do tomatoes grow fastest under fluorescent, incandescent, or natural light? (independent varaible)
The type of light the tomato plant is grown under
Uses of CFC? (4)
coolants, refrigerants, plastic foams, solvents, and as propellants in spray cans
explain the benefits of ozone in the atmosphere
living organisms on earth exist because they are protected from high levels of UVB by ozone, absorbs most harmful radiation before it reaches earths surface, protects our planet.
what are some important rules of laboratory safety?
look at pg19
Organize the following terms by arranging them from largest to smallest.macroscopic, submicroscopic, microscopic
macroscopic, microscopic, submicroscopic
Branches of Chemistry
organic, inorganic, physical, analytical, biochemistry, theoretical
ultraviolet radiation
overexposure from the sun has damaging/harmful effects to humans, animals and plants
Hw are we protected from high levels of UVB?
ozone
O^3
ozone
Quantitative Research
research that collects and reports data primarily in numerical form
control group
the group that is being compared, normal.
analytical chemistry
the identification of the components and composition of materials
organic chemistry
the study of all chemicals containing carbon
chemistry
the study of matter and how it changes
inorganic chemistry
the study of substances that, in general, do not contain carbon
physical chemistry
the study of the properties and changes of matter and their relation to energy
pure research
to gain knowledge for the sake of knowledge itself