8th Grade Science Unit 8

Big Idea:

The periodic table of elements classifies elements by its properties. Atoms join together to make chemical compounds and undergo chemical reactions to form new substances.

Student Expectations:

Priority TEKS

8.5(C) [Readiness] Interpret the arrangement of the Periodic Table, including groups and periods, to explain how properties are used to classify elements.

Focus TEKS

8.5(D) [Readiness] Recognize that chemical formulas are used to identify substances and determine the number of atoms of each element in chemical formulas containing subscripts.

8.5(E) [Readiness] Investigate how evidence of chemical reactions indicate that new substances with different properties are formed and how that relates to the Law of Conservation of Mass.

Ongoing TEKS

8.1(A) [Tools to Know] Demonstrate safe practices during laboratory and field investigations as outlined in the Texas Safety Standards.

8.1(B) [Tools to Know] practice appropriate use and conservation of resources, including disposal, reuse, or recycling of materials

8.2(A) [Tools to Know] Plan and implement comparative and descriptive investigations by making observations, asking well-defined questions, and using appropriate equipment and technology.

8.2(B) [Tools to Know] design and implement comparative and experimental investigations by making observations, asking well-defined questions, formulating testable hypotheses, and using appropriate equipment and technology

8.2(C) [Ways to Show] Collect and record data using the International System of Units (SI) and qualitative means such as labeled drawings, writing, and graphic organizers

8.2(D) [Ways to Show] construct tables and graphs, using repeated trials and means, to organize data and identify patterns

8.2(E) [Ways to Show] analyze data to formulate reasonable explanations, communicate valid conclusions supported by the data, and predict trends

8.3(A) [Ways to Show] In all fields of science, analyze, evaluate, and critique scientific explanations by using empirical evidence, logical reasoning, and experimental and observational testing, including examining all sides of scientific evidence of those scientific explanations, so as to encourage critical thinking by the student

8.3(B) [Ways to Show] use models to represent aspects of the natural world such as an atom, a molecule, space, or a geologic feature

8.3(C) [Ways to Show] identify advantages and limitations of models such as size, scale, properties, and materials

8.3(D) [Ways to Show] relate the impact of research on scientific thought and society, including the history of science and contributions of scientists as related to the content

8.4(A) [Tools to Know] ) use appropriate tools to collect, record, and analyze information, including lab journals/notebooks, beakers, meter sticks, graduated cylinders, anemometers, psychrometers, hot plates, test tubes, spring scales, balances, microscopes, thermometers, calculators, computers, spectroscopes, timing devices, and other equipment as needed to teach the curriculum

8.4(B) [Tools to Know] use preventative safety equipment, including chemical splash goggles, aprons, and gloves, and be prepared to use emergency safety equipment, including an eye/face wash, a fire blanket, and a fire extinguisher

Student Learning Targets:

• I will know the properties that are used to classify elements on the Periodic Table.
• I will understand how substances are written as chemical formulas.
• I will determine the number of atoms of each element in a chemical formula.
• I will observe and identify evidence of chemical reactions.
• I will recognize that after a chemical reaction takes place, the new substance has properties different from the original substances.
• I will define the Law of Conservation of Mass and recognize if a chemical equation follows this law.

Essential Questions:

• How are elements arranged on the periodic table?
• How can the arrangement of the periodic table help classify elements by their properties?
• How do electrons determine an element’s chemical properties?
• What evidence indicates that a chemical reaction has occurred?
• How does a balanced chemical equation relate to the Law of Conservation of Mass?

Extra Information:

Adopted Textbook: Texas STEM, McGraw-Hill

District Grading Policy

Texas Gateway Online Resource Center