Study Guides - Semester 1 Final

Semester 1 Final

Chemistry

Scientific Method

Scientific Measurement

Density and Buoyancy

Chapter 6 Study Guide

Chemical Reactions

1.     You should know how to write a chemical formula using your valence sheet.

Example:  Sodium chloride     Na ⁺¹   Cl ^-1   =     NaCl

       2.  A chemical change is when two or more substances react, or one substance

           decomposes.  In both cases something new is formed.  Evidence of a chemical

           change: 

         -  Temperature change (exothermic or endothermic)

         -  Color change

         - Precipitate forms

         - Gas produced (bubbles)

         - Fire/Explosion

3.     A physical change is a change in matter that does not produce a new substance like cutting paper or mixing salt and pepper.

4.     You should know the structure of a chemical formula.  Be able to label reactants, products, yields sign, subscripts and coefficients.

5.     Know that subscripts tell us the number of atoms of an element and coefficients tell us the number of molecules of a substance.

6.     Law of Conservation of Mass:  Matter is not created nor destroyed.

7.     You should know how to balance chemical equations.

8.     You should be able to identify the four major types of chemical reactions: Synthesis, Decomposition, Single Replacement, and Double Displacement.

9.     A catalyst is a substance that speeds up a reaction but is not involved in the chemical reaction.  Be able to identify the catalyst in a reaction.

Chapter 5 Study Guide

Chemical Bonding

1.     Using the Periodic Table, you should be able to draw the electron dot diagram for all of the elements covered in class.

2.     Ionic Bonds

A.     Know that an ion is a charged atom or group of atoms

B.     A polyatomic ion is what we call a charged group of atoms

C.      Atoms become charged when the gain or lose electrons.

D.     Atoms have positive charges when the lose electrons (mostly metals) and negative charges when they gain electrons (mostly nonmetals).

E.      Ionic Bonds form when electrons are transferred from one atom to another resulting in ions.  The opposite charges of the ions attract each other.  This is a very strong bond.

F.      You should know how to write chemical formulas using ion charges.  You should know how to name compounds using the chemical formula.  I will give you an ion list to use on the test.

G.      You should know the characteristics of ionic compounds:

1)     Ionic compounds form crystals because of the regular repeating pattern of ions.

2)     Conduct electricity when dissolved in water.

3)     High melting points

4)     Not flammable

5)     Almost all ionic compounds (salts) are formed from

a metal and a nonmetal bonding.

3.     Covalent Bonds

A.     Know that covalent bonds form when atoms share electrons.

B.     Usually form when nonmetals bond to other nonmetals.

C.      Sometimes atoms have to share lots of electrons when they bond (example: Nitrogen gas forms with a triple bond).

D.     Covalent molecules often have low melting points and burn easily (more flammable).

E.      Most covalent compounds do not conduct electricity in water like ionic compounds do.

Study Guide

Chapter 4 – The Periodic Table

Atomic Number if given the name, symbol, # of protons, or # of electrons

Number of Protons if given the name, symbol, atomic #, or # of electrons

Number of Electrons if given the name, symbol, atomic #, or #of protons

Atomic Mass (weight) if given the name or symbol

Element Symbol if given the element name

Element Name if given the symbol, atomic #, # of protons, or #of electrons

Period Number if given the symbol, atomic #, or # of protons or electrons

Number of Energy Levels if given the name, symbol, atomic #, or period

Group/Family if given the name, symbol, or atomic number

Number of Valence Electrons if given the name, symbol, or group/family

Properties and Valence Electrons for Alkali Metals, Alkaline Earth Metals, Halogens and Noble (Inert Gases)

Dmitri Mendeleev

Know where to find metals, nonmetals, and synthetic elements on the Periodic Table

Know that semimetals (metalloids) are good semiconductors because they can conduct electricity but not as well as metals (example: silicon)

Periods are horizontal rows that tell us the number or energy levels

Know major properties of metals and nonmetals

Bohr Models:  Be able to draw Bohr models for all elements up to 20.

Chapter 3 Study Guide

Chemistry – Properties of Matter

Solids, Liquids, and Gases

Study all Labs, Homework Sheets, Handouts, Graphic Organizers, and Notes.  You may also refer to Chapter 3 in your book.

Know definitions for the following terms:

Amorphous solid      Crystalline Solid    Solid

Fluid                            Gas                            Liquid                   Surface Tension        Temperature               Thermal Energy        Viscosity                Evaporation

Vaporization                Boiling

Know the definitions, molecular movement, and processes involved for each of the following:  (Example:  Melting – Solid to Liquid – Increase in Molecular Motion)

Melting                 Evaporation         Sublimation            Freezing

Condensation       Resublimation

Know that TEMPERATURE and PRESSURE are two factors that can affect the phase of matter.

Be able to explain the Gas Laws and give examples of each (Charles’s Law, Boyle’s Law, and Temperature/Pressure)

Know the effects of changing temperature, pressure, and volume of a gas.

Know that water freezes at 0 degrees C and boils at 100 degrees C.

Know your labs – why we did the labs and what they showed. Labs to know:  Freezing point lab, Marshmallow Madness Lab, Endothermic and Exothermic Lab, and all gas demos.

FROM CHAPTER 2 KNOW THE FOLLOWING:

Be able to define, describe, and identify chemical changes, physical changes, endothermic reactions and changes, and exothermic reactions and changes.

Know that electricity can be used to break molecules apart.  This is called electrolysis.  We used electrolysis to break bonds in water.  We saw gas bubbles produced and acids and bases produced.  That was the evidence that new substances had been formed – a chemical change.

                                                 Chapter 2 Test Study Guide

Properties of Matter

Concepts to Know:

1.     Everything is either energy or matter.

2.     Properties of matter are characteristics of a substance that help to identify that substance.  Physical properties are characteristics that can be observed and measured without breaking bonds or changing the substance chemically.   

Examples:  Color, shape, density, boiling point

Chemical properties can only be observed when a substance is changes chemically.

Examples: Reactivity with other chemicals, flammability

3.     An element is a pure substance that cannot be broken down into any other substance.  There are 92 naturally occurring elements in the universe.  Elements are organized on the Periodic Table of the Elements. 

4.     Atoms are the smallest particle of an element.

5.     Molecule – Two or more atoms chemically bonded.  Examples:  NaCl, CaCl₂, O₂, H₂O, H₂

6.     Compound – Two or more DIFFERENT types of atoms chemically bonded.  Example:  All of the examples for molecules BUT H₂.  H₂ is only made of one thing, Hydrogen.

7.     A mixture is two or more things combined together that have not been chemically bonded.  Solutions are a type of mixture where one thing dissolves into another. Examples: trail mix, salt water

8.     Heterogeneous Mixture – You can see the parts of the mixture

9.     Homogeneous Mixture – You can’t see the parts of the mixture.

10.  A physical change is a change in a substance that does not alter a substance chemically.  It’s still the same substance.

11.  A chemical change is a change where bonds are broken and new substances are formed.  Example: Burning wood, reacting Sulfuric Acid and Sugar.

12.  Law of Conservation of Matter says that whatever matter goes into a chemical reaction has to come out.

13.  Thermal Energy is the measure of the amount of movement of molecules in a substance.  The more movement, the more thermal energy, the higher the temperature.  Temperature is a measure of the thermal energy of an object.  We measure thermal energy (temperature) with a thermometer.

14.  Chemical Energy is energy stored in chemical bonds.

15.  Know the indicators of a chemical change and that a precipitate is a solid formed from a chemical reaction between two or more substances.

Study Guide – 8^th Grade Physical Science

Chapter 1 Test

To prepare for this test you will need to use your notes, labs, homework, and class work as well as your textbook. 

Scientific Inquiry (pages 6-15)

1.     Know what an inference is.  Be prepared to make inferences about a picture similar to the class and homework examples.

2.     Know what a hypothesis is.

3.     What are parameters in a scientific investigation?

4.     Know the definitions for manipulated and responding variable and be able to identify each in a given example.

5.     What is a controlled experiment?  Why is it important for experiments to be controlled?

6.     What is a scientific theory?  Know how theories and hypotheses are different.

Measurement and Equipment (pages 16 – 26)

1.     What is length?  What units do we use to measure length in science?

2.     What is weight?

3.     What is mass?  What units do we use to measure mass?

4.     How are weight and mass different?

5.     What happens to weight as gravity increases or decreases?

6.     What is volume?  What units do we use to measure volume?

7.     What is density?  What are the units for density?  What is the formula used to measure density? 

8.     Be ready to compare the relative densities of common objects discussed in class.

9.     Know graduated cylinder, beaker, balance, ruler, and Erlenmeyer flask.

Graphing in Science (pages 34 – 41)

1.     Know how to identify manipulated and responding variables in an experiment.

2.     Know how to take the data from a data table and graph the data putting the manipulated data on the horizontal axis and the responding variable on the vertical axis.  Label each axis.

3.     Know how to read a line graph.