AP Chemistry Unit 5

Big Idea:

The chemical elements are fundamental building materials of matter, and all matter can be understood in terms of arrangements of atoms. These atoms retain their identity in chemical reactions.

Chemical and physical properties of materials can be explained by the structure and the arrangement of atoms, ions, or molecules and the forces between them.

Student Expectations:

Focus Standards

Enduring understanding 1.B: The atoms of each element have unique structures arising from interactions between electrons and nuclei.

Essential knowledge

• 1.B.1: The atom is composed of negatively charged electrons, which can leave the atom, and a positively charged nucleus that is made of protons and neutrons. The attraction of the electrons to the nucleus is the basis of the structure of the atom. Coulomb’s law is qualitatively useful for understanding the structure of the atom.
• 1.B.2: The electronic structure of the atom can be described using an electron configuration that reflects the concept of electrons in quantized energy levels or shells; the energetics of the electrons in the atom can be understood by consideration of Coulomb’s law.

Enduring understanding 1.C: Elements display periodicity in their properties when the elements are organized according to increasing atomic number. This periodicity can be explained by the regular variations that occur in the electronic structures of atoms. Periodicity is a useful principle for understanding properties and predicting trends in properties. Its modern-day uses range from examining the composition of materials to generating ideas for designing new materials.

Essential knowledge

• 1.C.1: Many properties of atoms exhibit periodic trends that are reflective of the periodicity of electronic structure.
• 1.C.2: The currently accepted best model of the atom is based on the quantum mechanical model.

Enduring understanding 1.D: Atoms are so small that they are difficult to study directly; atomic models are constructed to explain experimental data on collections of atoms

Essential knowledge

• 1.D.1: As is the case with all scientific models, any model of the atom is subject to refinement and change in response to new experimental results. In that sense, an atomic model is not regarded as an exact description of the atom, but rather a theoretical construct that fits a set of experimental data.
• 1.D.3: The interaction of electromagnetic waves or light with matter is a powerful means to probe the structure of atoms and molecules, and to measure their concentration.

Enduring understanding 1.E: Atoms are conserved in physical and chemical processes.

Essential knowledge

• 1.E.1: Physical and chemical processes can be depicted symbolically; when this is done, the illustration must conserve all atoms of all types.
• 1.E.2: Conservation of atoms makes it possible to compute the masses of substances involved in physical and chemical processes. Chemical processes result in the formation of new substances, and the amount of these depends on the number and the types and masses of elements in the reactants, as well as the efficiency of the transformation

Ongoing Standards

Science Practice 1 The student can use representations and models to communicate scientific phenomena and solve scientific problems.

Science Practice 2 The student can use mathematics appropriately.

Science Practice 3 The student can engage in scientific questioning to extend thinking or to guide investigations within the context of the AP course.

Science Practice 4 The student can plan and implement data collection strategies in relation to a particular scientific question. (Note: Data can be collected from many different sources, e.g., investigations, scientific observations, the findings of others, historic reconstruction and/or archived data.)

Science Practice 5 The student can perform data analysis and evaluation of evidence.

Science Practice 6 The student can work with scientific explanations and theories.

Science Practice 7 The student is able to connect and relate knowledge across various scales, concepts and representations in and across domains.

Student Learning Targets:

• Analyze data relating to electron energies for patterns and relationships. [LO 1.6, SP 5.1]
• Express the law of conservation of mass quantitatively and qualitatively using symbolic representations and particulate drawings. [LO 1.17, SP 1.5]
• Apply conservation of atoms to the rearrangement of atoms in various processes. [LO 1.18, SP 1.4]
• Describe the electronic structure of the atom, using PES data, ionization energy data, and/ or Coulomb’s Law to construct explanations of how the energies of electrons within shells in atoms vary. [LO 1.7, SP 5.1, SP 6.2]
• Justify the selection of a particular type of spectroscopy to measure properties associated with vibrational or electronic motions of molecules. [LO 1.15, SP 4.1, SP 6.4]
• Explain the distribution of electrons in an atom or ion based upon data. [LO 1.5, SP 1.5, SP 6.2]
• Analyze data relating to electron energies for patterns and relationships. [LO 1.6, SP 5.1]
• Explain the distribution of electrons using Coulomb’s Law to analyze measured energies. [LO 1.8, SP 6.2]
• Explain why a given set of data suggests, or does not suggest, the need to refine the atomic model from a classical shell model with the quantum mechanical model. [LO 1.12, SP 6.3]
• Given information about a particular model of the atom, determine if the model is consistent with specified evidence. [LO 1.13, SP 5.3]
• Predict and/or justify trends in atomic properties based on location on the periodic table and/or the shell model. [LO 1.9, SP 6.4]
• Analyze data, based on periodicity and the properties of binary compounds, to identify patterns and generate hypotheses related to the molecular design of compounds for which data are not supplied. [LO 1.11, SP 3.1, SP 5.1]
• Predict properties of substances based on their chemical formulas, and provide explanations of their properties based on particle views. [LO 2.1, SP 6.4, SP 7.1]
• Predict and/or justify trends in atomic properties based on location on the periodic table and/or the shell model. [LO 1.9, SP 6.4]

Essential Questions:

• Why do Mylar balloons that are filled with hydrogen gas keep their pressure longer than balloons filled with helium gas?
• How does the arrangement of the outer electrons in an atom determine how the atom bonds to others and forms materials?

Extra Information:

Adopted Textbook:

District Grading Policy

Texas Gateway Online Resource Center