Chemistry Unit 1

Unit Overview

In middle school, students are introduced to the structure of the atom and its composition, the periodic table and identifying areas on the table such as metals, non-metals, and inert gases. They have been introduced to symbols for elements and some very basic chemical equations. They will expand on these ideas, incorporating atomic number, mass, and properties of elements based on the patterns of electrons in their outermost shell.

Standards

Next Generation Science Standards – High School (NGSS-HS):

PS1-1. Use the periodic table as a model to predict the relative properties of elements based on the patterns of electrons in the outermost energy level of atoms.

Examples: properties that could be predicted from patterns could include reactivity of metals, types of bonds formed, numbers of bonds formed, and reactions with oxygen. Focus on main group elements. Each atom has a charged substructure consisting of a nucleus, which is made of protons and neutrons, surrounded by electrons.

PS1-2. Construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.

Examples: the reaction of sodium and chlorine, of carbon and oxygen, carbon and hydrogen. Focus on chemical reactions involving main group elements and combustion reactions.

Science and Engineering:

• Construct an explanation based on valid and reliable evidence obtained from a variety of sources (including students’ own investigations, models, theories, simulations, peer review) and the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future.

Crosscutting concepts:

• Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.

California Science Standards -- Chemistry:

1a. Students know how to relate the position of an element in the periodic table to its atomic number and atomic mass.

1b. Students know how to use the periodic table to identify metals, semimetals, nonmetals, and halogens.

1c. Students know how to use the periodic table to identify alkali metals, alkaline earth metals and transition metals, trends in ionization energy, electronegativity, and the relative sizes of ions and atoms.

1d. Students know how to use the periodic table to determine the number of electrons available for bonding.

1e. Students know the nucleus of the atom is much smaller than the atom yet contains most of its mass.

1 h. Students know the experimental basis for Thomson’s discovery of the electron, Rutherford’s nuclear atom, Millikan’s oil drop experiment, and Einstein’s explanation of the photoelectric effect.

2a. Students know atoms combine to form molecules by sharing electrons to form covalent or metallic bonds or by exchanging electrons to form ionic bonds.

2b. Students know chemical bonds between atoms in molecules such as H2, CH4, NH3,H2CCH2, N2, Cl2, and many large biological molecules are covalent.

2e. Students know how to draw Lewis dot structures.

Investigation and Experimentation Standards:

d. Formulate explanations by using logic and evidence.

g. Recognize the usefulness and limitations of models and theories as scientific representations of reality.