Important Information

FIRE DRILL INFORMATION:Take a left out of door→→go to field

MRS. PROVENZOLA

IPC LAB SAFETY AND SCIENTIFIC METHOD

Important Information

• Notebook Requirements:– 3 Ring Binder with DividersCourse policy sheetLab Safety Rules etNotes by UnitGraded Work

LAB SAFETY

Please also refer to handouts for more detailed information!!

Lab Safety

• Read Laboratory Safety Rules Handout

/

LAB SAFETY

• Safety symbols- http://www.chem.queensu.ca/Safety/whmissym.htm

• http://www.chem.queensu.ca/Safety/Safety_Symbols.htm• http://www.chem.queensu.ca/Safety/TDGA_Symbols.htm• Safety contract- MUST BE RETURNED BY FRIDAY!• Safety quiz- Friday, 8/27 QUIZ grade—must make an

80% or higher to be able to go to lab.

THE NATURE OF SCIENCE

Using the Scientific Method

WHAT IS SCIENCE?

• IT IS THE STUDY OF NATURAL PATTERNS.

Science Categories

LIFE

PHYSICAL

EARTH

EXPLANATIONS CAN CHANGE OVER TIME

Investigations include:ObservationExperimentationModeling

The Scientific MethodA logical, organized way of solving problems

that help answer questions

• Define the Problem• Collect Background

Information• Form a Hypothesis• Test the Hypothesis• Make and Record

Observations/Analyze Data

• Draw a Conclusion

Defining the Problem & Collecting Background Information

• Identify the problem.• Example: What are

the effects of acid rain on salamanders?

• Collect information about the problem.

• Example: We should know the normal development of salamanders as well as the characteristics of areas that are affected by acid rain.

FORMULATE A HYPOTHESIS

• An educated guess that is based on PRIOR KNOWLEDGE or background

• A proposed answer to the question or problem.

• A statement that can be tested

TESTING THE HYPOTHESIS p.1/2

• An experiment is a controlled procedure designed to test a hypothesis.

• In an experiment, one variable, or condition, is changed and the response of another variable is measured.

THE EXPERIMENT p.2/2

• Independent variable: the condition that is varied (or changed).

• Dependent variable: the condition that responds to the changes in the I.V.

• To be a controlled experiment, it must have two identical groups:

• Experimental group- the group that is exposed to the changes in the I.V.

CONTROL GROUP

• Control group- the group that is NOT exposed to changes to ensure that the results that occur are indeed a result of the independent variable.

• It is the standard for comparison

• Ex. A room is kept at 70OC for the plants. The plants receive the same soil mix amount of water, and the type of pot and size of pots….. on and on...

MAKING & RECORDING OBSERVATIONS p. 1/4

• Must keep careful records.

• Must state how the experiment was planned, carried out, materials & equipment used, and how long it took.

• Must record all observations made.

MAKING & RECORDING OBSERVATIONS p.2/4

• May include: drawings, tables, graphs, diagrams, written observations, photographs or even sound recordings.

0102030405060708090

Are

a A

Are

a B

Are

a C

Are

a D

Species 1Species 2Species 3

OBSERVATIONS VS. INFERENCES p.4/4

Observation: an examination of something in nature. Detected by any of the five senses.

Inference: Inference- a judgement based on your observation. It is a personal opinion.

DRAWING CONCLUSIONS p.1/2

• The answer to a scientific question is formulated by drawing a conclusion based on data (scientific facts collected during the experiment)

• Statistics help form the conclusion.

CONCLUSIONS p.2/2

• Before accepting conclusions, scientists retest their hypotheses several times. Later other scientists repeat the experiment until the hypothesis and the conclusion are supported or rejected.

Writing a Conclusion

• Restate the problem

• Restate the hypothesis

• Restate the variables

• Define the trends

• Accept or reject the hypothesis and why

• Sources of error

THEORY

• A theory is a set of related hypotheses that have been tested and confirmed many times, by many scientists. It unites and explains a broad range of observations.

• When a hypothesis explains why “natural” events occur through observations and investigations over a long period of time, it becomes a theory. Example: Theory of Evolution

THEORY

• At all times, however, theories and principles are subject to revision or replacement by a new theory or principle that provides a better or more complete explanation.

Scientific Law

• When a hypothesis explains how “facts of nature” occurs, it becomes scientific principle or law. Example: Law of Gravity

• Statement that ALWAYS seems to be true.

Standards of Measurement

Standard

• An exact quantity that people agree on.

It’s used for

comparison

Technology

• Applied science helping people.

Measurements

• Must have a number and a unit!

Gram……. Meters…….

Liters…….. Seconds…..

Joules……..

System International of Units

• (SI) – improvement on the metric system

• Understood WORLDWIDE!

• Based on multiples of 10

• Prefixes indicate multiples

LENGTH --

• Measures the distance between 2 points.

Meters

Volume

• The amount of space an object occupies.

Liters

Volume of Solid

• Obj. #7c. Volume can be measured by:

1) length x width x height = V (regularly shaped solid object)

2) 3.5 x 2 x 4 = 28cm3

4cm

3.5 2 cm

Volume

2) water displacement method volume of water & object - - water alone = V

(irregularly shaped solid object)

6.6 ml water

----------

--------

----

----------- ___. -------. -------. -------. ------------------ ___. -------. -------. -------. ------- ------------- ___. -------. -------

--

WaterAnd object

------------------

------

---8.4 ml

8.4-6.6 =--------

1.8 ml object

Volume

• using a graduated cylinder (fluids)

Read the bottom of the meniscus

-- the curved surface of liquid.

Mass

• The amount of matter.

Measured in Grams

Density

• Mass per unit volume.

•g/L or g/cm3

I’m a derived

Unit!

Time

• Interval between 2 events.

Measured in seconds

Temperature

•Thermometer•SI standard – KELVIN•Also in Fahrenheit and Celsius

Communicating with Graphs

Graphs

• Visual Display of information or data

Music preferences…Is there a difference?

Line Grahps

• dependent variable changes due to change in the independent variable

Y-axis = dependent X-axis = independent

The relationship between the vapor Pressure of water and its temperature

Line graphs showChange over time

Makes sense and unitsof measurements are consistent

Bar Graph= compare info collected by counting

Circle/Pie Graph

• Shows how a whole is broken into smaller pieces.

What area of the

budget gets the

least amount of money?