Chapter 1 Sections 2,3 Pages 10-21

What are independent and dependent variables? Scientific method, a series of problem-solving procedures that help scientists conduct experiments. A hypothesis, a testable explanation of a situation that can be supported or disapproved by careful experiments. If……, then….., because….

How does experimentation and investigation differ? Experimentation, an experiment is classified as an organized procedure that involves making observations and measurements to test a hypothesis. Independent variable, the factor that is changed by the experimenter Dependent variable, the factor that is affected by changes in the independent variable Control, used to show that the results of an experiment are a result of the factor being tested (changed) Constants, factors that do not change in an experiment Specific amounts needed to keep experiment valid, and reliable Allows for experiment to be repeatable, with the same results

How does experimentation and investigation differ? Investigation, Earth Scientists Cannot control aspects of an experiment, i.e. rainfall, temperature Research is used Involves observations and collecting data No control Can lead to designs of future experiments based on observations

How does experimentation and investigation differ? Investigations Experiment Variables cannot be controlled Variables need to be controlled No control control Research Background information Observations and collecting data Analysis of data and observation Conclusion must be supported by data and observations; must prevent bias or prejudge

How does experimentation and investigation differ? Analysis and conclusions Processes, data, and conclusions must be examined to eliminate influence by expectations or beliefs Bias, prejudice Graphs, charts, tables used to display data, which are analyzed to produce a conclusion

What are the differences between mass and weight? Measurements used in Scientific investigations System of standard units, Le Systeme International d’Unites (SI), a modern version of the metric system Length is measured in meters (m) 1 cm = 1/100 of meter 1cm = 10 mm 1km = 1000m

What are the differences between mass and weight? Mass, the amount of matter in object; it never changes Gram, kilogram, metric ton Weight, measurement of the gravitational force on an object; it changes Newton (N) Area, amount of surface within set boundaries m2

What are the differences between mass and weight? Volume, the amount of space an object takes up

What are the differences between mass and weight? Volume, the amount of space an object takes up 1 cm3 = 1 mL

What are the differences between mass and weight? Density, the measure of the amount of matter that occupies a given space Density = Mass/Volume Time, the interval between two events Seconds Measured with a stopwatch or clock

What are the differences between mass and weight? Temperature, a measure of the average kinetic energy of the particles that make up a material Celsius (0C); room temp 21 0C, human body temp is 37 0C SI unit of temperature is kelvin (K); Absolute zero 0 K or -273 0C Convert the following: 500C to K -490C to K 77K to 0C 500K to 0C Convert Temperatures 500C to K 50 + 273 323K -490C to K -49+273 224K 77K to 0C -273+77 -1960C 500K to 0C -273+500 2270C

What is scientific notation and how is it used? Scientific notation, used to express very large or very small numbers Move the decimal to the left for large numbers Move the decimal to the right for small numbers Example: 4,567,000 becomes 4.567000 then 4.567 x 106 0.00000005436 becomes 00000005.436 then 5.436 10-8 101 = 10 10-1 = 1.0 102 = 100 10-2 = 0.1

Communication in Science Section 2

Why is precise communication crucial in science? Video: Anti-Vaxxers Fund Study - Zero Link Between Vaccinations And Autism https://www.youtube.com/watch?v=koTSE2mSrfs Scientists need to be truthful and accurately (ethics) report their methods and results. To keep scientists ethical, scientists in the same field will conduct a peer review to verify each other’s results and examine procedures and conclusions for bias. Lab Reports, see handouts (format, rubric)

When is it appropriate to use a graph or a model? Graphs can easily show the relationship/trends/patterns among data Line graphs, independent variable is plotted on the x-axis; the dependent variable plotted on the y-axis Circle graphs (pie charts) shows a fixed quantity; the slices are usually presented as percentages (%) Bar graphs, represent quantitative data

When is it appropriate to use a graph or a model? Scientific model, is an idea picture, a system, or a mathematical expression that represents a concept/topic. Models can change when more data is gathered.

What are the differences between scientific theories and scientific law? Scientific theory, is an explanation based on observations during repeated investigations. Must meet the following criteria Is consistent with observations and supported with experimental or factual evidence Testable predictions Simplest explanation of observations Can be changed or modified with new data Scientific law, is a principle that describes the behavior of a natural phenomenon Rule of nature observed to be the same every time Theories are often used to explain scientific law