7. Energy is exchanged or transformed in all chemical reactions and physical changes of matter. As a basis for understanding this concept:
a. How to describe temperature and heat flow in terms of the motion of molecules (or atoms).
b. Chemical processes can either release (exothermic) or absorb (endothermic) thermal energy.
c. Energy is released when a material condenses or freezes and is absorbed when a material evaporates or melts.
d. How to solve problems involving heat flow and temperature changes, using known values of specific heat and latent heat of phase change.
e. How to apply Hess's law to calculate enthalpy change in a reaction.
REACTION RATES
8. Chemical reaction rates depend on factors that influence the frequency of collision of reactant molecules. As a basis for understanding this concept:
a. The rate of reaction is the decrease in concentration of reactants or the increase in concentration of products with time.
b. How reaction rates depend on such factors as concentration, temperature, and pressure.
c. The role catalysts and inhibitors play in increasing or decreasing the reaction rate.
d. The definition and role of activation energy in a chemical reaction.
CHEMICAL EQUILIBRIUM
9. Chemical equilibrium is a dynamic process at the molecular level. As a basis for understanding this concept:
a. How to use LeChatelier's principle to predict the effect of changes in concentration, temperature, and pressure.
b. Equilibrium is established when forward and reverse reaction rates are equal.
c. How to write and calculate an equilibrium constant expression for a reaction.
--note: Standard 10; Organic Chemistry and Biochemistry is not currently covered in our curriculum so it is not included here
NUCLEAR PROCESSES
11. Nuclear processes are those in which and atomic nucleus changes, including radioactive decay of naturally occurring and human-made isotopes, nuclear fission, and nuclear fusion. As a basis for understanding this concept:
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 E=mc squared) 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 know how the nucleus changes in each type of decay.
e. Alpha, beta, and gamme radiation produce different amounts and kinds of damage in matter and have different penetrations.
f. How to calculate the amount of a radioactive substance remaining after an integral number of half lives have passed.