# Science 8

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Eighth grade science is an introduction to physical science. Topics include volume and mass, mass changes in a closed system, characteristic properties, and solubility. In this laboratory-based class, students further refine their application of the scientific method and improve their ability to observe and record; to make and refine hypotheses; and to design, run, and write up lab-based inquiries. In an eagerly anticipated final project students use the skills, theories, and techniques learned throughout the year to separate “sludge,” a mixture of numerous solids, liquids, and gases. The year ends with the formulation of the atomic theory of matter.  It is a smooth transition to the high school science program as 9th grade picks up where we left off on the atom and the nature of bonding. Students are expected to be thoroughly engaged in inquiry, curious, respectful and invested in their learning.

## Units

Unit Essential Questions Content Skills and Processes Assessment Resources Multicultural Dimension
Volume and Mass

•What methods can we employ to measure matter?
•What are the shortcomings of volume as a measure of matter?
•What does mass measure?
•How is mass different from weight?
•What limits do our measuring devices impose on our confidence of results?

*Volume and mass are the two different ways in which we measure matter
*Volume is not best way to compare or measure matter due to its dependence on temperature and pressure
*Mass is amount of matter contained in an object,
*Volume is the amount of space an object occupies,
both mass and volume involve counting and comparing units of measure,
*Weight is force imposed upon an object by gravity
*Mass stays constant within normal ranges of temperature and pressure
*Measuring devices have certain and discrete sensitivities,
a measurement must contain a magnitude, units and uncertainty

*Work in a laboratory,
*Collect gas using liquid displacement
*Safely operate alcohol burners and micro-burners
*Determine the uncertainty of measuring devices
*Measure volume of regular and irregular solids
*Measure mass using single pan balance
*Compare objects using mass, volume
*Determine best mode of comparing matter
*Record data in clear organized manner
*Compare class data
*Formulate conclusions based on class data

*Lab notebooks
*Daily preparation
*Class participation
*Quizzes, tests
*Projects
*Self-assessment through reflection

Introductory Physical Science, 7th edition, Haber-Schiam,Cutting, Kirksey, Pratt

Mass Changes in Closed Systems

•Does mass change when substances undergo different changes?
•What are the essential attributes of a Law of Nature?

*Conservation of Mass
*Experimental evidence will lead studets to this fundamental law of nature

*Accurately read and use a single pan balance
*Use uncertainty
*Create histograms using class data
*Identify and explain changes in state and matter
*Indirectly measure the mass of a gas
*Analyze class data
*Draw conclusions based on experimental evidence
*Express very large numbers and very small numbers using scientific notation
*Explain fundamental concepts of a Law of Nature

*Laboratory performance
*Written exam
*Practical exam

Introductory Physical Science, 7th edition, Haber-Schiam,Cutting, Kirksey, Pratt

*The program is designed to engage the learning styles of all participants and address the needs of students of diverse cultural backgrounds.
*Inquiry, although not identical in style from culture to culture, is an important part of how all cultures extend knowledge.
*The informality of the lab allows a teacher to work with an individual or a pair of students who might be struggling with a given skill or concept.
*Students work with other students whose cultural background may be quite different from their own during the term. As they work together to solve a problem, they must talk, plan, and work out a plan for successful completion of the task at hand. This model for open inquiry enables students to share their learning with fellow students.

Characteristic Properties of Matter

How do we know when two substances are different?
What is the difference between a property of an object and a property of a substance?
What is the relationship between the mass of an object and the volume of an object?

density, boiling point, freezing point are independent of the size and shape of objects,
density, boiling point and freezing point are characteristic properties of matter.

1- determine the freezing points of substances such as water, salt water, naphthalene, paradichlorobenzene,
2- determine the melting points of the same substances,
3- organize and collect data over time.
4- graph data using appropriate scale, units and labels.
5- interpret data on a graph.
6- determine boiling points of substances.
7- distinguish between substances using boiling point.
8- determine density of regular solids, irregular solids.
9- determine density of liquids and gases.
10- use significant figures in division and multiplication calculations.
11- properly use scientific notation.
12- distinguish and identify unknown substances by comparing experimental data with accepted values.

comprehensive unit test,
practical laboratory exam in which they must distinguish between three unknown liquids,
cooperative group project in which they will create a classroom density gradient using liquids of unknown density and miscibility

Introductory Physical Science, 7th edition, Haber-Schiam,Cutting, Kirksey, Pratt

Refer to Fall term

Solubility

How can we use solubilty to distinguih bewteen substances?
What is the maximum amount of solute that can dissolve in a given amount of solvent?
How does solubility change with temperature?

that solubility is a characteris property of both the solute and the solvent,
like density solubility changes with temperature,
the dependence on temperature is useful in separating solutes in a solution,
when a subsatnce dissolves in a solvent it distributes itself evenly throught the column of solvent,
concentration is a way to expressing the quantity of substance dissolved in a fixed amount of liquid,
when a metal dissolves in a strong acid a gas is produced,
liquids are soluble in liquids,
solids are soluble in liquids and other solids,
alloys are mixtures of solids,
gases are soluble in liquids,

make solutions of specific concentrations,
determine relative concentrations of colorful solutions based on shade,
compare concentraions of saturated solutions,
distinguish between saturated substances by comapring their temperatures,
compare different solvents,
collect gases generated by dissolving different metals and salts in strong acids,
differentiate the gases generated by comparing realtive density and flammabilities,
determoine the solubility of carbon dioxide and ammonia in water

*Written exam

Introductory Physical Science, 7th edition, Haber-Schiam,Cutting, Kirksey, Pratt

Separation of Mixtures

1- How can we tell the difference between a pure substance and a mixture?
2- How can two liquids in solution be separated from one another?
3- How can two dissolved solids be separated from one another?
4- How can a pigment be separated into its component parts?

1- mixtures can be separated into component parts called pure substances
2- mixtures and pure substances are different from each other
3- dissolved solids can be separated.
4- differences in density, boiling point, and solubility can be used to separate substances.
5- paper chromatography is used to separate a pigment from a liquid.

1- separate two or more liquids by fractional distillation.
2- explain how fractional distillation is used for industrial uses.
3- separate a mixture of soluble and insoluble solids.
4- separate a mixture of soluble solids.
5- separate a solid pigmnet from a solution.

1- comprehensive unit test.
2- practical laboratory exam in which they must distinguish between a collection of unknown solids and liquids called Sludge.
3- cooperative group work in the laboratory.
4- periodic quizzes.
5- review of lab write-ups.

Introductory Physical Science, 7th edition, Haber-Schiam,Cutting, Kirksey, Pratt

*Tone and topics of the classroom laboratory allow students of all cultural backgrounds to find a level of engagement that is comfortable.
Refer to Fall term