Dual Credit Chemistry 1st Semester Study Guide

Accuracy

the closeness of a series of results to the actual correct value

Precision

The degree to which repeated measurements show the same result.

Observation

sensory based, determined using senses.

Inference

A conclusion reached on the basis of evidence and reasoning

Hypothesis

An educated guess

independent variable

the variable the scientist changes or the manipulated variable

dependent variable

the variable that is measured in an experiment

Constant

variables that stay the same

Control group

a standard against which change is measured

Quantitative

numerical data

Qualitative

data that is collected using your senses, describes a particular quality.

Matter

physical substance in general, as distinct from mind and spirit; (in physics) that which occupies space and possesses rest mass, especially as distinct from energy.

Substance

a particular kind of matter with uniform properties.

Element

each of more than one hundred substances that cannot be chemically interconverted or broken down into simpler substances and are primary constituents of matter. Each element is distinguished by its atomic number, i.e., the number of protons in the nuclei of its atoms.

Compound

a thing that is composed of two or more separate elements; a mixture.

homogeneous mixture

solid, liquid, or gas that contains two or more substances blended evenly throughout

heterogeneous mixture

has components whose proportions vary throughout the sample

physical properties

The color, shape, texture, phase or state of a material

Density

the ratio of the mass of a substance to its volume

physical change

changes affecting the form of a chemical substance, but not its chemical composition

chemical properties

a property or characteristic of a substance that is observed during a reaction in which the chemical composition or identity of the substance is changed

chemical change

a usually irreversible chemical reaction involving the rearrangement of the atoms of one or more substances and a change in their chemical properties or composition, resulting in the formation of at least one new substance

Law of Conservation of Mass

states that mass is neither created nor destroyed during a chemical reaction but is conserved

thermal energy

the internal energy of an object due to the kinetic energy of its atoms and/or molecules

Temperature

A measure of how hot or cold something is.

Solubility

a chemical property referring to the ability for a given substance, the solute, to dissolve in a solvent.

atomic number

the number of protons in the nucleus of an atom

mass number

the total number of protons and neutrons in the nucleus of an atom

Isotopes

a form of a chemical element whose atomic nucleus contains a specific number of neutrons, in addition to the number of protons that uniquely defines the element.

atomic mass

The average mass of all the isotopes of an element

Groups

a column of elements in a periodic table

Periods

the name given to a horizontal row of the periodic table

Alkane

an acyclic saturated hydrocarbon

Alkyl group

An alkyl group is a functional group of an organic chemical that contains only carbon and hydrogen atoms, which are arranged in a chain. They have general formula CnH2n+1

Functional group

Specific substituents or mareties within molecules that are responsible for the characteristic chemical reactions of those molecules

Structural isomers

Any of two or more compounds with identical chemical formulas, such as propyl alcohol and isopropyl alcohol, that differ structurally in the sequence in which the atoms are linked

Isomerism

the relation of two or more compounds, radicals, or ions that are composed of the same kinds and numbers of atoms but differ from each other in structural arrangement

aromatic hydrocarbons

a hydrocarbon with sigma bonds and delocalized pi electrons between carbon atoms forming a circle.

Phenyl group

a cyclic group of atoms with the formula C6H5

Polymer

A large molecule consisting of many repeating chemical units or molecules linked together.

polyunsaturated

having in each molecule many chemical bonds in which two or three pairs of electrons are shared by two atoms.

What type of graph would best illustrate the percentage of students who like different subjects?

Pie graph

What type of graph would best illustrate the effect of the amount of caffeine on heart rate?

Line graph

What type of graph would best illustrate the number of students who are freshmen, sophomores, juniors, and seniors at HHCA?

Bar graph

List three examples of unsafe lab behavior and what the appropriate procedure would be to fix this behavior.

1) not wearing safety goggles | wearing safety goggles

2) eating, drinking, and chewing gum | do it outside

3) mixing unknown chemicals | ask your teacher first

I notice that my students do better on tests when I give them cookies beforehand. Write a hypothesis for an experiment that could investigate this observation. List the independent variable, dependent variable, constants, control group and experimental group.

If I give my students cookies beforehand, then they will do better on tests.

* The independent variable is the cookies that are given to the students within the experiment.

* The dependent variable is test scores.

* The constants are the amount of students.

* The control group is the students who do not eat cookies before their tests.

* The experimental group is the students who eat cookies before the test.

787,000

7.87 x 10^5

4,999,000

4.999 x 10^6

0.00413

4.13 x 10^-3

0.000000112

1.12 x 10^-7

6.9 x 10^-3

.0069

7.009 x 10^6

7,009,000

1.01 x 10^2

101

5.0553 x 10^4

50,533

20 degrees Celsius to Fahrenheit

68

300 Kelvin to Celsius

26.85

98 degrees Farenheit to Kelvin

309.817

150 cm to mm

1,500mm

71g to kg

.071kg

1200 ks to s

1200000s

191 days to seconds

1.65 x 10^7 seconds

32 lbs to grams

14515 grams

21 mm to yds

0.0229659 yds

Draw the flowchart for how matter can be classified (see example on p. 3 in notes)

MATTER (MIXTURE(HOMOGENEOUS MIXTURE)(HETEROGENEOUS MIXTURE)) (PURE SUBSTANCE(COMPOUND)(ELEMENT))

What is the biggest difference between compounds and mixtures?

Compounds are always homogeneous, whereas mixtures can be homogeneous or heterogeneous.

Explain the three principles of kinetic molecular theory.

The simplest kinetic model is based on the assumptions that: (1) the gas is composed of a large number of identical molecules moving in random directions, separated by distances that are large compared with their side; (2) the molecules undergo perfectly elastic collisions (no energy loss) with each other and with the walls of the container, but otherwise do not interact; and (3) the transfer of kinetic energy between molecules is heat.

What is a solution? What are the two parts to a solution?

A solution is a homogeneous type of mixture of two or more substances. a solute and a solvent.

What are the three types of solutions?

isotonic, hypotonic, hypertonic

Summarize our current understanding of the structure of the atom. Include where the mass and volume in the atom are mainly located, as well as where protons, neutrons and electrons are found.

Electrons are found in shells or orbitals that surround the nucleus of an atom. Protons and neutrons are found in the nucleus. They group together in the center of the atom.

What is the electron cloud? Explain how electrons move within the cloud, their energy, and what the outermost electrons are called.

Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. Electrons are tiny, negatively charged particles in an atom that move around the positive nucleus at the center.

What does the group number on the periodic table tell you? What does the period number tell you?

The elements in each group have the same number of electrons in the outer orbital. Number of energy levels in each period.

Describe the different characteristics between metals, nonmetals, and metalloids on the periodic table.

Metallic: Distinguishing luster (shine) | Malleable and ductile (flexible) as solids | Conduct heat and electricity | Metallic oxides are basic (ionic) | form cations in aqueous solution

Nonmetallic: Non-lustrous, various colors | Brittle, hard or soft | Poor conductors | Nonmetallic oxides are acidic, covalent | Form anions, oxyanions in aqueous solution

Metalloids: Silicon | Boron | Arsenic | Antimony | Germanium | Phosphorus

Name compounds.

To name a compound, the cation name and the anin name are added together.

Draw compounds from the name.

draw chemical structure.

Identify isomers

there are just two types (structural and stereoisomer) and several subtypes.

combustion reaction

hydrocarbons combust with oxygen to produce carbon dioxide and water

CxHy + O2 -> H2O + CO2

CH4 + O2 -> H2O + CO2

C5H12 + O2 -> H2O +CO2

What is a major difference between inorganic and organic compounds?

Organic compounds contain carbon; few inorganic compounds do.

What is the reason why there are so many organic compounds?

Carbon atoms can form stable covalent bonds with other carbon atoms.

Which statement is not correct? Functional groups are

the parts of molecules used to differentiate classifications of organic molecules.

Identify the correct statement: The alkanes represent one family of organic compounds

that is composed of carbon and hydrogen.

The benzene ring as a branch is called a ______ group.

phenyl

Which of the following is an alcohol?

CH3CH2OH

Cycloalkanes are

None of these statements is correct.

What is a characteristic shared by the alkanes?

flammable

Naphthalene is used as:

Moth repellent

Complete combustion of pentane produces ___________.

CO2 and H2O

All of the members of the alkane series of hydrocarbons have the general formula

CnH2n+2

Which of the following compounds is a structural isomer of 2-methyl butane?

pentane

What is the longest carbon chain for the compound shown?

9

The IUPAC name for the following compound is _______________.

3-methylpentane

Which of the following is the structural formula of 1-bro mo-2,2-dimethylpropane?

c.

Which of the following cycloalkanes contains a total of 10 carbon atoms?

1-isopropyl-2-methylcycloheptane

Alkanes are _____ in water and _____ than water.

insoluble, less dense

alkanes react readily with

none of the choices

cis-1,2 dimethylcyclohexane and trans- 1,2-dimethylcyclohexane are examples of what type of isomers?

more than one response is correct

Name a difference between a saturated and an unsaturated hydrocarbon.

Saturated hydrocarbons do not contain multiple bonds between carbons, but unsaturated hydrocarbons do contain multiple bonds.

Which characteristic relates to alkenes but not the other hydrocarbon families?

double bonds

what number would be used to indicate the double bond position in the IUPAC name for CH3=CH-CH2-CH2-CH3

1

In the IUPAC name for the following compound, the -Br group is located at what position of the compound shown?

CH3BrCHCH=CH2

3

Which of the following compounds is trans-3-hexene?

c.