laboratory safety- exit do’s (you must have atleast 4 in this column) –1. –2. –3. –4....
TRANSCRIPT
Laboratory Safety- Exit
• Do’s (You must have ATLEAST 4 in this column)– 1.– 2.– 3.– 4.
– Print pictures to add to your posters!
• Do not’s (You must have ATLEAST 4 in this column)– 1.– 2.– 3.– 4.
Do Now- JournalMake as many observations as you can about this picture. Think about this…
• What is the scientific method?
• What are the 5 senses?
Chapter 1
“STUDYING SCIENCE”
1.1 Science Skills and Methods
• Objectives• Identify and use science skills.•Describe a controlled experiment.
•Apply a scientific method.
What is Science?• Science is a way to
gather and organize information about the natural world.
• Scientists do this by using such skills as observing, inferring, estimating, measuring, predicting, classifying, hypothesizing, recording, organizing and analyzing.
Science Skills
• Although there are many different fields of scientific study, all scientists use these basic science skills to search for knowledge about the natural world.
Observe• The most direct way
to gain knowledge about something in nature is to observe.
• When you observe, you use one or more of your senses.
Your senses are sight, touch, taste, smell, and hearing.
Look at the objects in Figure 1.1.
1.1List as many
observations as you can about each object.
Which senses do you use most
often?
Infer• When you suggest a
possible explanation for an observation, you make an inference, or you infer.
• You often can make more than one inference to explain the same observation.
What can you infer about these
symbols?
Estimate• When you estimate,
you make a careful guess.
• Estimating skills are used to gather information when exact measurements aren't needed.
Estimate the number of
blocks in the cube above.
Measure• When you need exact information
about an observation, you measure.
Count the number of crystals for a
more exact measurement.
Predict• When you
predict, you state what you think might happen in the future.
• Predictions are based on past experiences and observations.
Classify• When you classify,
you group things together based on how they are alike.
• You can group things in many different ways, such as size, color, shape, or any other characteristic.
What are some different ways to
classify these rocks?
Hypothesize• When you state a
hypothesis, or hypothesize, you suggest a possible answer to a question or problem.
• Your answer is based on information that you know.
Think of a hypothesis as an explanation that states why something may always occur.
Testing Your Hypothesis
• You can test a hypothesis by conducting an experiment.
• Your observations, research, and the results of experiments should support your hypothesis.
• What if it doesn’t?
Record and Organize
• Careful record keeping is an important part of science.
• You can record and organize data in a number ways such as using tables, charts, graphs, diagrams and flowcharts
Analyze• After data are recorded
and organized, you need to analyze it.
• When you analyze data, you look for trends or patterns to see whether or not your data supports your hypothesis.
DATA
Experiments• A good way to get
answers to questions in science is to do experiments.
• Experiments need to be carefully designed to test an idea, prediction, hypothesis, or inference.
Controlled Experiments
• Most experiments are controlled experiments.
• A controlled experiment has two test groups-the control group and the experimental group.
Scientists repeat experiments to check their data and
conclusions.
Control & Experimental Groups
• The control group is a standard by which any change can be measured.
• In the experimental group, all the factors except one are kept the same as those in the control group.
• The factors that are kept the
same are called constants.
• The factor that is changed by
the person doing the experiment
is called the variable.
Question:
WHY DOES MY GRANDMOTER ADD SALT TO THE WATER
BEFORE SHE COOKS SPAGHETTI?
A Controlled Experiment
Hypothesis: If adding salt to water will then it will increase the temperature at which water
boilsEach beaker has the same amount of distilled water.
Each beaker of water was heated
at the same setting.
Salt was added to the experimental
beaker.
The water in the beakers were stirred for one
minute.
A thermometer measured the temperature in both beakers.
The unsalted water boiled at 100°C. The salted water boiled
at a higher temperature.
Do the observations and results support the hypothesis?
YES
Scientific Method• The phrase scientific
method can be used to describe how scientists find out about the natural world.
• The scientific method refers to a systemized method of using science skills to test ideas, inferences, predictions, and hypotheses.
Scientific Method• Think of a science problem or
question.
• Now, write a description of an experiment that will solve it.
• Use the steps in Figure 1.6 on page 8, with the exception of analyze data and conclude to help.
Designing and Planning an Experiment
Decision Making
Facts, Theories, and Laws
• In science, a fact is a true statement. Science facts are always based on observations, studies, and repeated tests and experiments.
• Gathering facts is an important part of developing a good hypothesis.
Facts, Theories, and Laws
• A scientific law or theory is a hypothesis that has been thoroughly tested and no contradictions have been found.
Darwin’ s theory of evolution
Facts, Theories, and Laws
• A Scientific law describes how an event occurs.
• Scientific laws are usually stated in mathematical terms.
Models in Science• Models are used to
represent real objects. Some models are drawings, such as diagrams and maps.
• Often models are built from real materials and are working models of the real object.
Plane Mode
l
All models are plans from which real
objects can be built
Chapter 1Section 2
Measuring with Scientific Units
1.2 Measuring With Scientific Units
• Objectives• Identify the base units used in the SI system.• Explain the use of scientific notation.
• Compare volume, mass and density.
• Measure length, mass and temperature using SI Units.
Measuring With Scientific Units
• Did you know that your feet get bigger during the day?
SI Units• The system of
measurement used throughout most of the world today is the Systeme International d'Unites, or SI system.
• It is also called the metric system.
Basic SI Units of measure
SI UnitsUnlike other systems of measurement, SI units are based on multiples of ten.
Prefixes such as kilo- or centi- indicate units larger or smaller than the basic SI units.
LengthThe basic SI unit of length is the meter
(m).
You will measure many distances that are less than 1 meter. The numbers to the top of this metric ruler
represent centimeters.
How many centimeters is this pencil? 19 cm.
Volume• Volume is the
amount of space that something occupies.
• The SI unit of volume is the cubic meter (m3).
• A convenient unit for everyday use is the liter (L).
A graduated cylinder is used to measure
liquid volumes.
Meniscus
Mass• Mass is the
amount of matter that an object contains.
• The basic SI unit of mass is the gram (g).
To determine an object's mass, you use
a tool called a balance.
Density
• Mass is related to another important quantity called density.
• Density tells you how much matter is packed into a given volume of space.
• The units of density are grams of matter per cubic centimeter (g/cm3).
The number of mL the water level rises is equal to the volume of the submerged
object
Density
You can calculate the density of an object by using this mathematical formula:Density = g/ml
Example: Calculate the density of a piece of aluminum if a 50 mL block weighs 135 g.
Solution: Apply the formula:
Density = 135 g = 2.70 g/mL 50 mL
Temperature• When you are healthy,
your normal body temperature is about 98.6o Fahrenheit (F).
• On the Celsius scale, which is used internationally and in science, your normal body temperature measures about 37o Celsius (C).
On the Celsius scale, water freezes
at 0oC and boils at 100oC
Time• The basic SI unit of
time is the second (s).
• Amounts of time less than one second are measured in milliseconds (ms).
• One millisecond is 1/1,000 of one second.
Scientific Notation• Scientists often work with
very long numbers.• To save time, they write
these numbers in scientific notation.
• In scientific notation, a number is written as the product of two numbers. 2.68 X 1015 or 1.5 X 10-12
• For example, the distance from the earth to the moon is about 384,400 km (238,855 miles) or in scientific notation, 3.844 x 105 km.
Skills WorkoutList some things that you think are
so big or so small that scientific notation would be needed to write
their measurement.
The thickness of a piece of paper = app. 1.0 X 10-4 m
The circumference of the Earth = app 4 .0 X 104 km
The distance from Earth to Pluto = app. 6.0 X 109
The size of a virus = app. 2.0 X 10-9
Chapter 1Section 3
Graphing
1.3 Graphing• Objectives
– Describe three types of graphs.– Identify the parts of a line graph.– Analyze data and plan a graph.
Graphing• A graph is a picture of data that
shows numerical data in diagram form. A graph makes it easier to understand information.
Kinds of Graphs• Three kinds of graphs are circle, bar
and line graphs.
• Each kind of graph shows numerical data in a different way.
Circle Bar Line
Circle Graphs• A circle graph is
a circle divided into parts.
• This kind of graph makes it easy to compare how one part relates to the whole amount.
What two gases make up most of the air? Which of the two is
there more of?
Bar Graphs• The wide columns
on a bar graph are used to compare measurements, such as weight, height, and length, about groups or individual items.
Which city has the highest yearly temperature? Which
has the lowest?
• Line graphs are useful for comparing sets of numerical data.
• They also show change and patterns, or trends in data.
Line Graphs
Compare and contrast Raul and Rosa's
growth patterns. Who is taller at age 8? At age 14?
Chapter 1Section 4
Science Tools & Technology
1.4 Science Tools & Technology
• Objectives– Describe the connections in science.– Give examples of technological tools.– Compare science and technology.– Infer why tools influence science
research.
Connections in Science• Have you ever wondered what your
fingernails are made of?
• Why a light turns on when you flip a switch?
• How television and radio signals reach your home?
• Getting the answers to these questions involved scientific study of why and how things happen in the natural world.
Connections in Science• Science has many divisions, but they are all
connected. For example…• The study of matter can be identified as two
connected sciences, chemistry and physics.
• Chemistry is the study of matter and its changes.
• Physics and Physical Science
are the study of energy and
how it affects matter.
Tools and Technology
• Science research explores why and how things happen in the natural world.
• Technology is the use of physical science principles to help answer those questions.
• Scientists use technological tools, both simple and complex to gather data about the natural world.
Radio Telescop
e
Wind Tunnel
• The rapid calculations done by a computer can help people identify things that are too tiny or too distant to see.
The spectrogram produced by a spectroscope indicates what kind of matter makes up a star or other object in space.
Some of the tools that make it possible:
To study how matter and energy interact, physicists "shoot" tiny particles of matter at a larger particle in a particle accelerator.
Electrophoresis gel - Biochemists use electricity to separate the proteins and nucleic acids that make up living things.
Check and Explain pg. 251. The specialty biochemistry combines biology and
chemistry. Chemical reactions are studied in chemistry and life processes are studied in biology.
2. Spectroscopes are used to study objects in space. Microscopes are used to study very small objects
3. Science explains how and why things happen in the natural world; technology is the use of science principles to solve practical problems.
4. Some tools enable people to observe objects that are very small or very far away. By using tools, scientists are able to make more detailed observations.
Prehistoric Technology
• When you think of the word technology, what do you think of?
• Actually, technology based on the principles of physical science is ancient.
Prehistoric Technology
• The stone tools made about 1.9 million years ago in Africa are one example.
• The technology in a stone ax is a simple machine called a wedge.
A gold ring of Pharaoh Ramses II
(1290-1224 B.C.) and a stone
cutting tool made by Homo
habilis.
Prehistoric Technology
• Millions of years ago, people learned to control and use fire for cooking and heating.
• Many other technologies became possible once fire was controlled.