CHEMISTRY
Investigation and Experimentation
Chemistry is the physical science that describes matter, i.e., its composition, structure, physical
and chemical transformations, and the energies associated with these transformations. Three
descriptive dimensions are routinely intertwined:
1. Macro-scale observations describe and classify matter and energy on the human
sensory level; for example, phases, homogeneity (physical properties such as color, density,
volatility), and chemical reactivity, alone and in combination with other substances.
2. Nano-scale models describe and classify matter and energy beyond the human sensory
level; for example, atoms, subatomic particles, interparticle bonds and bond making/breaking,
reaction energies, rates and chemical equilibrium. Energy is the currency of change, and
spontaneous reactions achieve lower energy states and greater stability.
3. Chemical symbolism represents both the macro- and nano-scale perspectives.
The chemistry standards are designed to provide students with a detailed understanding of the
interaction of matter and energy. This interaction is investigated through the use of laboratory
techniques, manipulation of chemical quantities, and problem-solving applications. Scientific
methodology is employed in experimental and analytical investigations, and concepts are
illustrated with practical applications that should include examples from environmental, nuclear,
organic, and biochemistry content areas. Technology, including graphing calculators, computers,
and probeware, are employed where feasible.
Students will understand and use safety precautions with chemicals and equipment. The
standards emphasize qualitative and quantitative study of substances and the changes that occur
in them. In meeting the chemistry standards, students will be encouraged to share their ideas, use
the language of chemistry, discuss problem-solving techniques, and communicate effectively.
The chemistry standards continue to focus on student growth in understanding the nature of
science. This scientific view defines the idea that explanations of nature are developed and tested
using observation, experimentation, models, evidence, and systematic processes. The nature of
science includes the concepts that scientific explanations are based on logical thinking; are
subject to rules of evidence; are consistent with observational, inferential, and experimental
evidence; are open to rational critique; and are subject to refinement and change with the
addition of new scientific evidence.
Students will investigate and understand that experiments in which variables are measured,
analyzed, and evaluated produce observations and verifiable data. Key concepts include:
a. Designated laboratory techniques;
b. Safe use of chemicals and equipment;
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c. Proper response to emergency situations;
d. Manipulation of multiple variables, using repeated trials;
e. Accurate recording, organization, and analysis of data through repeated trials;
f. Mathematical and procedural error analysis;
g. Mathematical manipulations (SI units, scientific notation, linear equations, graphing, ratio and
proportion, significant digits, dimensional analysis);
h. Use of appropriate technology including computers, graphing calculators, and probeware, for
gathering data and communicating results; and
i. Construction and defense of a scientific viewpoint (the nature of science).
Atomic Theory and the Periodic Law
Atomic and Molecular Structure
The periodic table displays the elements in increasing atomic number and shows how
periodicity of the physical and chemical properties of the elements relates to atomic
structure. Students will investigate and understand:
a. The role of
Periodic Law.
b. How to relate the position of an element in the periodic table to its atomic number and atomic
mass.
c. How to use the periodic table to identify metals, metalloids, and nonmetals.
d. How to use the periodic table to identify alkali metals, alkaline earth metals and transition
metals, as well as trends in ionization energy, electronegativity, and the relative sizes of ions
and atoms.
e. How to use the periodic table to determine the number of electrons available for bonding.
f. The nucleus of the atom is much smaller than the atom yet contains most of its mass.
Honors Extension. Students will investigate and understand:
g. How to use the periodic table to identify the lanthanide, actinide, and transactinide elements
and know that the transuranium elements were synthesized and identified in laboratory
experiments through the use of nuclear accelerators.
h. The experimental basis for Thomson’s discovery of
the electron,
Millikan’s oil drop experiment, and Planck’s and Einstein’s explanations of the photoelectric
effect.
i. The patterns for allowed (quantized) energy level of electrons within atoms and their
relationship to the Periodic Table and the chemical reactivity of the elements.
j. The experimental basis for the development of the quantum theory of atomic structure and the
historical importance of the Bohr model of the atom.
k. Spectral lines are the result of transitions of electrons between energy levels and that these
lines correspond to photons with an energy content quantified by Planck’s relationship
(E-hy).
l. The wave-particle duality of electromagnetic radiation to include frequency, wavelength, and
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the quantized nature of the photon.
m. Electromagnetic radiation as a tool, as a probe into the nature of atoms/molecules and their
constituent particles.
Chemical Bonds
Biological, chemical, and physical properties of matter result from the ability of atoms to
form bonds from electrostatic forces between electrons and protons and between atoms and
molecules. Chemical change requires breaking bonds and forming new bonds to form new
substances while maintaining the elemental identity of each atom. Students will investigate
and understand:
a. Atoms combine to form molecules by sharing electrons to form nonmetallic covalent bonds or
by exchanging electrons to form metallic ionic bonds (cations + and anions -.
b. Chemical bonds between atoms in molecules such as H2, CH4, NH3, HCCH2, N2, Cl2, and
many large biological molecules are covalent.
c. Salt crystals, such as NaCl, are repeating patterns of positive and negative ions held together
by electrostatic attraction.
d. Atoms and molecules in liquids move in a random pattern relative to one another because the
intermolecular forces are too weak to hold the atoms or molecules in a solid form.
e. How to draw Lewis dot structures.
Honors Extension. Students will investigate and understand:
f. How to predict the shape of simple molecules and their polarity from Lewis dot structures.
g. The use of valence shell electron pair repulsion theory (VSEPR) to predict molecular shape
from Lewis electron structures.
h. How electronegativity and ionization energy relate to bond formation.
i. How to identify solids and liquids held together by Van der Waals forces or hydrogen bonding
and relate these forces to volatility and boiling/ melting point temperatures.
Conservation of Mass and Stoichiometry
The conservation of atoms in chemical reactions leads to the principle of conservation of
mass and the ability to calculate the mass of products and reactants. Students will
investigate and understand:
a. How to describe chemical reactions by writing balanced equations.
b. The quantity one mole is set by defining one mole of carbon 12 atoms to have a mass of
exactly 12 grams.
c. One mole containes Avogadro’s number 6.02 x 1023 particles (atoms or molecules).
d. How to determine a compound’s empirical formula from elemental mass data.
e. How to determine the molar mass of a molecule from its chemical formula and a table of
atomic masses and how to convert the mass of a molecular substance to moles, number of
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particles, or volume of gas at standard temperature and pressure.
f. How balanced equations (stoichiometric equations) indicate the molar relationships of the
reactants consumed and the products produced.
g. How to calculate the masses of reactants and products in a chemical reaction from the mass of
one of the reactants or products and the relevant atomic masses.
Honors Extension. Students will investigate and understand:
h. A mole as the formula mass expressed in grams.
i. How to calculate percent theoretical yield as a reflection of non-ideal reality in reaction
efficiencies.
j. How to identify reactions that involve oxidation and reduction and how to balance oxidationreduction
reactions.
Gases and Their Properties
The kinetic molecular theory describes the gas phase motion of atoms and molecules as a
means to explain the properties of gases under certain conditions. Students will investigate
and understand:
a. The random motion of molecules and their collisions with a surface create the observable
pressure on that surface.
b. The random motion of molecules explains the diffusion of gases.
c. How to apply the gas laws to relations between the pressure, temperature, and volume of any
amount of an ideal gas or any mixture of ideal gases.
d. The values and meanings of standard temperature and pressure (STP).
e. How to convert between the Celsius and Kelvin temperature scales.
f. There is no temperature lower than 0 Kelvin.
Honors Extension. Students will investigate and understand:
g. The kinetic theory of gases relates the absolute temperature of a gas to the average kinetic
energy of its molecules or atoms.
h. How to solve problems by using the ideal gas law in the form PVı=ınRT.
i. How to apply
Graham’s law to predict diffusion of gases.
j. Avogadro’s Hypothesis and molar volume at STP.
k. The Law of Combining Volumes as a component of gaseous reaction stoichiometry.
Acids and Bases
Acids, bases, and salts are three classes of compounds that form ions in water solutions.
Students will investigate and understand:
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a. The observable properties of acids, bases, and salt solutions.
b. Acids are hydrogen-ion-donating and bases are hydrogen-ion-accepting substances.
c. Strong acids and bases fully dissociate and weak acids and bases partially dissociate.
d. How to use the pH scale to characterize acid and base solutions.
Honors Extension. Students will investigate and understand:
e. The Arrhenius, Brønsted-Lowry, and Lewis acid–base definitions.
f. Strong electrolytes as ionic compound solutions yield high ion concentrations.
g. Weak electrolytes dissolve as molecules which then react with water (hydrolysis) and yield
partial ionization producing a low concentration of ions.
h. Non-electrolytes dissolve completely as neutral molecules and yield no ions.
i. How to calculate pH from the hydrogen-ion concentration.
j. Buffers stabilize pH in acid–base reactions.
Solutions
Solutions are homogeneous mixtures of two or more substances. Students will investigate
and understand:
a. The definitions of solute and solvent.
b. How to describe the dissolving process at the molecular level by using the concept of random
molecular motion.
c. Temperature, pressure, and surface area affect the dissolving process.
d. How to calculate the concentration of a solute in terms of grams per liter, molarity, parts per
million, and percent composition
e. How to use the concentration expressions of molarity, molality, and mole fraction.
Honors Extension. Students will investigate and understand:
f. The relationship between the molality of a solute in a solution and the solution’s depressed
freezing point or elevated boiling point.
g. How molecules in a solution are separated or purified by the methods of chromatography and
distillation.
Chemical Thermodynamics
Energy is exchanged or transformed in all chemical reactions and physical changes of
matter. Students will investigate and understand:
a. How to describe temperature and heat in terms of the motion of molecules (or atoms).
b. If the total strength of all new bonds formed in a reaction exceeds the total strength of the
bonds broken, heat energy is released in an exothermic reaction.
c. If the total strength of all bonds broken exceeds the strength of all new bonds formed, heat
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energy must be absorbed in an endothermic reaction.
d. Energy is released when a material condenses or freezes and is absorbed when a material
evaporates or melts.
e. How to solve problems involving heat flow and temperature changes, using known values of
specific heat and latent heat of phase change.
Honors Extension. Students will investigate and understand:
f. How to apply Hess’s law to calculate enthalpy of reaction or heat of reaction expressed as _Hr
and relate _Hr to the molar quantities of reagents in the stoichiometric equation.
g. The validity, utility and application of Hess’s Law.
h. How to use enthalpies of formation, _Hf , to calculate _Hr.
i. Entropy and its significance in energy changes of chemical and physical change.
j. How to use the Gibbs Free Energy Equation _G = _H - T_S, and the meaning of reaction
spontaneity.
k. _G and the position of equilibrium
Reaction Rates (Kinetics)
Chemical reaction rates depend on factors that influence the frequency of collision of
reactant molecules. Students will investigate and understand:
a. The rate of reaction is the decrease in concentration of reactants or the increase in
concentration of products with time.
b. How reaction rate depends on such factors as concentration, temperature, and pressure and is a
direct effect of collision frequency and orientation.
c. The exponential increase in reaction rate as the absolute temperature increases
d. The nature and behavior of catalysts.
Honors Extension. Students will investigate and understand:
e. The energy of activation, Eact, and its negative exponential impact on reaction rate (reaction
rate decreases exponentially as Eact increases).
Chemical Equilibrium
Chemical equilibrium is a dynamic process at the molecular level. Students will investigate
and understand:
a. At equilibrium the forward rate and reverse rate are equal, and the relative proportions of
reactants and products are constant.
b. The position of equilibrium is directly related to _Gr.
c. The position of equilibrium can be changed by adding/removing reagents and/or changing
pressure or temperature.
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d. How to use LeıChatelier’s principle to predict equilibrium position shifts when the system is
disturbed.
Honors Extension. Students will investigate and understand:
e. How to write and calculate an equilibrium constant expression for a reaction.
Organic Chemistry and Biochemistry
The bonding characteristics of carbon allow the formation of many different organic
molecules of varied sizes, shapes, and chemical properties and provide the biochemical
basis of life. Students will investigate and understand:
a. Large molecules (polymers), such as proteins, nucleic acids, and starch, are formed by
repetitive combinations of simple subunits.
b. The bonding characteristics of carbon that result in the formation of a large variety of
structures ranging from simple hydrocarbons to complex polymers and biological molecules.
c. Amino acids are the building blocks of proteins.
Honors Extension. Students will investigate and understand:
d. The system for naming the ten simplest linear hydrocarbons and isomers that contain single
bonds, simple hydrocarbons with double and triple bonds, and simple molecules that contain
a benzene ring.
e. How to identify the functional groups that form the basis of alcohols, ketones, ethers, amines,
esters, aldehydes, and organic acids.
f. The R-group structure of amino acids and how they combine to form the polypeptide backbone
structure of proteins.
Nuclear Processes
Nuclear processes are those in which an atomic nucleus changes, including radioactive
decay of naturally occurring and human-made isotopes, nuclear fission, and nuclear fusion.
Students will investigate and understand:
a. Protons and neutrons in the nucleus are held together by nuclear forces that overcome the
electromagnetic repulsion between the protons.
b. The energy release per gram of material is much larger in nuclear fusion or fission reactions
than in chemical reactions. The change in mass (calculated by Eı=ımc
2
) is small but
significant in nuclear reactions.
c. Some naturally occurring isotopes of elements are radioactive, as are isotopes formed in
nuclear reactions.
d. The three most common forms of radioactive decay (alpha, beta, and gamma) and how the
nucleus changes in each type of decay.
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e. Alpha, beta, and gamma radiation produce different amounts and kinds of damage in matter
and have different penetrations.
Honors Extension. Students will investigate and understand:
f. How to calculate the amount of a radioactive substance remaining after an integral number of
half-lives have passed.
g. Protons and neutrons have substructures and consist of particles called quarks.