SCIENCE SKILLS Chapter 1

1.1 What is Science I. Science from Curiosity A. Involves asking questions about nature and finding solutions. B. Begins with curiosity and ends with discovery. C. Is a system of knowledge and methods used to find that knowledge. D. Scientific knowledge is discovered and then applied in ways that improve peoples lives. 1

II. Science and Technology A. Technology is the use of knowledge to solve practical problems. B. Science and technology are interdependent. Advances in one lead to advances in the other.

III. Branches of Science A. Divided into social science and natural science 1. Natural Science is generally divided into physical science, Earth and space science, and life science. a) Two main branches of physical science. 1)Chemistry – The study of the composition, structure, properties, and reactions of matter. 2)Physics – The study of matter and energy and their interaction through forces and motion.

b) The two areas of Earth and space Science. 1)Geology – The foundation of Earth science. The study of the origin, history and structure of Earth. 2)Astronomy – The study of the universe beyond Earth, including the sun, moon, planets and stars. c) Life Science 1)Also known as biology. It is the study of living things and how they grow, survive and reproduce.

IV. The Big Ideas of Physical Science or the basic rules of nature. A. Space and Time – The universe is very old and very big. B. Matter and change – A very small amount of universe is matter. 1. Matter: a) Has volume and mass. b) Usually in the form of a solid, liquid or gas. c) Matter is made up of atoms.

C. Forces and Motion – Forces cause changes in motion. D. Energy – Exists in many forms. 1. Kinetic energy is energy an object has due to motion. 2. Potential energy is energy that is stored as a result of position or shape. 3. When one form of matter changes into another form, energy is absorbed. 4. Energy can be transferred from one object to another, but can never be destroyed.

 1.2 Using a Scientific Approach I. Scientific Methods A. Organized plans for gathering, organizing and communicating information. B. The goal is to solve a problem or to better understand an observed event.

II. Steps in the scientific method. A. Make Observations – Information that is obtained through using your senses. B. Form a Hypothesis – A proposed answer to a question. An educated guess. C. Testing a Hypothesis – Perform experiments to test the accuracy of your hypothesis. 1. Manipulated variable or independent variable is a variable that causes change in another. 2. Responding variable or dependent variable is the variable that changes in response to the manipulation. 3. Controlled experiment is an experiment in which only one variable is manipulated.

D. Drawing a Conclusion – An answer or result based on data collected. 1. Conclusions can be changed if they are not correct. E. Developing a Theory – A scientific theory is a well-tested explanation for a set of observations or experimental results. III. Scientific Law – Is a rule of nature. It describes an observed pattern in nature without attempting to explain it.

IV. Scientific Models – Make it easier to understand things that might be too difficult to observe directly. A. A model is a representation of an object or event. B. If data shows that a model is wrong it must be changed or replaced with a new model.

V. Working Safely in Science. A. Follow safety precautions at all times. B. Read all steps before starting an experiment. C. Follow teacher and text book instructions exactly. D. You share responsibility for your safety and that of your classmates.

 1.3 Measurement I. Using Scientific Notation A. Makes very large or very small numbers easier to work with. B. A shortcut for expressing numbers with a lot of zero’s C. A way of expressing a value as the product of a number between 1 and 1o and a power of 10. D. Math Skills – Example using scientific notation.

II. SI Units of Measurement A. Scientists use a set of measuring units called SI. B. SI – The International System of Units. C. SI is a revised version of the metric system. III. Base and derived units A. SI is built upon seven metric units known as base units. B. Derived units are made from combining more than one base unit.

C. An example of a derived unit is density. 1. Density = mass/volume 2. Density is the ratio of an objects' mass to its volume. D. Metric Prefixes 1. Metric prefixes indicate how many times a unit should be multiplied or divided by 10.

Common Prefix Units millim0.001 centic0.01 decid0.1 base meter, liter, grams 1 dekadk10 hectoh100 kilok1000 megaM1,000,000

E. To convert from one unit to another use a conversion factor. 1. Example: Prefix kilo, 1 kilo=1000m This gives you two possible conversion factors. 1 km/1000m 1000 m/1km a) If you’re converting from smaller to larger, then the number should get smaller. Multiplying 1km/1000m yields a smaller number. b) Multiplying 1000m/1km will give a larger number.

2. Example: If you want to convert 8848 meters into kilometer. a) You are converting meters to kilometers, smaller to larger. b) You should use 1km/1000m So: 8848 m x 1 km/1000m = km c) The meters cancel out and you are left with kilometers.

IV. Limits of Measurement. A. Precision – A gauge of how exact a measurement is. 1. The precision of a calculated answer is limited by the least precise measurement used to calculate it. B. Significant figures – All the digits that are known in a measurement. C. Accuracy – The closeness of a measurement to the actual value of what is being measured.

V. Measuring Temperature A. A thermometer is an instrument used to measure temperature. B. Converting from one scale to another. 1. °C=5 ⁄9 (°F −32) 2. °F=9⁄5 (°C) K=°C + 273

 Important Temperature Readings Water Boils 212°F 100°C 373k Human Body Temperature 98.6°F 37°C 310k Average Room Temperature 68°F 20°C 293k Water Freezes 32°F 0°C 273k

 1-4 Presenting Scientific Data I. Scientific data becomes meaningful only when they are organized and communicated. II. Organizing Data A. Scientists use data tables and graphs. 1. Data tables are simple ways to present data relating variables.

III. Line Graphs show changes that occur in related variables. A. Manipulated variable is plotted on the x-axis or the horizontal line. B. Responding variable is plotted on the y-axis or the vertical line. C. Slope or the steepness of the line shows the ratio of a vertical change to the corresponding horizontal change. 1) Formula: Slope = rise / run. Rise = the change in the y-variable. Run = the corresponding change in the x-variable.

D. Direct proportion is the relationship in which the ratio of two variables is constant. E. Inverse proportion is the relationship in which the product of the two variables is a constant. IV. Bar graph is used to compare a set of measurements, amounts, or change. V. Circle graph is a divided circle that shows how a part or share of something relates to the whole.

VI. Communicating Data A. Crucial part of scientific investigation. B. Scientists can communicate results by writing in scientific journals or speaking at conferences.