MIDTERM REVIEW

WORKSHEET

OPEN BOOK 30 POINT QUIZ

To Be Turned in at your Midterm

Components of an ExperimentIndependent Variable: The factor in the experiment that is purposely changed.“I” the examiner change

Dependent Variable: Measurable factor that responds to a change in the independent variable.Dependent depends on the independent.

Constant- Conditions that remain the same during the course of the experiment

Control- A standard for comparison, not in every experiment.

**Remember how to choose the Independent variable (what “I” the examiner change), Dependent variable (depends on the independent- usually measurable), Constants (remains the same), Control (standard to compare to) etc.

How to Graph “Effect of IV on DV”

Scientific Method

• A series of logical steps that are followed to solve a problem.

• Uses critical thinking

PIE CHART- parts of a whole, %

Bar Graph- Comparison of similar data for several different items or events

LINE GRAPH:For displaying data that changes over time

Metric Conversion of Units

Base:MeterLiterGram

by

Metric Conversion Units

Accuracy vs Precision

MATTER

Substance Mixture

Element Compound HeterogeneousMixture

HomogeneousMixture

‘Solutions’

Atom: Molecule:

Examples: Examples: Examples: Examples:

MATTERPURE

SUBSTANCEMIXTURE

• Matter that has a fixed composition (makeup) and definite properties (chemical and physical).

• Matter that is a combination of two or more pure substances

that do not have a fixed composition or definite

properties.• Are chemically combined- so they can’t be physically separated.

• Are NOT chemically combined, so components CAN be separated.

Compound:

A substance made of atoms of 2 or more different

elements that are chemically combined.

Element:

A substance that can’t be broken down into simpler substances

Each element is made of only one kind of atom.

ATOM:

The smallest unit of an element that maintains the properties of the element.

MOLECULE:H2O O2

The smallest unit of a

substance that behaves like the substance.

(Keeps all of its physical and chemical properties)

Changes of State

PHYSICAL CHANGE

• Dissolving• Sanding• Crushing• Breaking/cutting• Bending/twisting• Mixing

• CHANGE OF STATE– Melting/evaporating– freezing

A change of matter from one form to

another without a change in chemical properties

CHEMICAL CHANGE • ODOR

• COLOR CHANGE• BUBBLING• FIZZING• FOAMING• HEAT PRODUCED• SOUND PRODUCED

A change of matter that

occurs when a substance changes

composition by forming one or

more new substances

CANNOT BE REVERSED BY PHYSICAL CHANGES

Changes of State

Buoyant Force

The buoyant force is equal to the weightof the liquid displaced.

Archimedes Principle

An object that is submerged in a fluid is buoyed up by a force equal to the weight of the fluid that is displaced

Density

D = M/V

mass volume

Pascal’s PrincipleA change in pressure at any point in an enclosed fluid at rest is transmitted equally throughout the fluid.

VISCOSITY

PressureTemperature

andVolume

Boyle’s Law, Charle’s Law of Gases:Constant Temperature: If you decrease the volume you

will increase the pressure.Constant Pressure: If you increase the temperature the

volume will increase (if it could).

Bohr’s Model of the Atom

Like planets around the sun

METALS

NONMETALS

Periodic Table

METALS•Alkali Metals•Alkali Earth Metals•Transitions Metals•‘Other Metals’

NON-METALS•‘Other Non-Metals’•Halogens•Noble Gases

Form Cations +

Form Anions -

ATOMIC NUMBER =

Number of Protons =

Number of Electrons

MASS NUMBER = (Atomic Mass, Atomic Weight)

Number of Protons +Number of Neutrons

Atomic Number +Number of Neutrons

Using the Periodic Table

ELEMENT NAME AND

SYMBOL

ATOMIC #

MASSNUMBER(round to nearest whole

number)

NUMBERof

PROTONS

NUMBERof

NEUTRONS

NUMBERof

ELECTRONS

NUMBER of

VALENCEELECTRONS

OXIDATIONNUMBER

and CHARGE(+ or -)

(P) 15

38Gallium

(Ga) 31

Using the Periodic Table

ELEMENT NAME AND

SYMBOL

ATOMIC #

MASSNUMBER(round to nearest whole

number)

NUMBERof

PROTONS

NUMBERof

NEUTRONS

NUMBERof

ELECTRONS

NUMBER of

VALENCEELECTRONS

OXIDATIONNUMBER

and CHARGE(+ or -)

Phosphorus (P)

Strontium(Sr)

Gallium (Ga) 31 70 31 39 31 3 +3

Remember: Atomic number is = the number of ProtonsIn a Neutral Atom the number of = protons is = to the number of – electrons

All the Mass in in the nucleus- The Mass Number is = Protons + NeutronsValence Electrons = outer shell = Group 1 has 1, Group 2 = 2, Group 13 = 3, Group 14 = 4 etc

Oxidation # = # of electrons taken in (-) or give away (+) to get to a full valence shell.

Dalton's Atomic Theory

• 1) All matter is made of atoms. Atoms are indivisible and indestructible.

• 2) All atoms of a given element are identical in mass and properties

• 3) Compounds are formed by a combination of two or more different kinds of atoms.

• 4) A chemical reaction is a rearrangement of atoms.

This chart and a Periodic Table will be provided to you- you just have to know how to READ it and USE it.

Practice with your class worksheets, quizzes and homeworks

Organic CompoundA COVALENTLY bonded compound

that contains carbonMost common elements:

C,H

ANY organic compound that is burned will release Carbon in some form

Hydrocarbon

An organic compound made of only carbon and hydrogen

Simplest Hydrocarbon:Methane

Alkanes, Alkenes, Alkynes

Only Single Bonds C-CAt least one Double C=CAt least one Triple C=C

POLYMERS Polymers are substances that are

made up of a large number of repeating units (monomers). There are both synthetic and naturally occurring

polymers.

Formed by chemical reactions in which these monomers are joined in a certain order, forming a chain.

Natural Polymers:Proteins - silk, collagen, keratin, DNARepeating units of amino acidsCarbohydrates - cellulose, starch. Made up of repeating units of glucose

Other Natural polymers: Rubber (hydrocarbon base) and silicones (alternating silicon and oxygen).

Cross Linking of Polymers:

Cross linking: Makes the polymer elastic, flexible by helping it to go back to its original shape after stretching.Too many cross links and the polmer becomes rigid (like the back of a desk chair), or may even crack/break

Counting Atoms

2H2O

= 2 Molecules of H2O, or 4 atoms of H, 2 atoms of O,

6 atoms all togetherCo