TEKS Addressed: 6.1A, 6.1B, 6.2A, 6.2B, 6.2C, 6.2D, 6.2E, 6.3A, 6.3B, 6.3C, 6.3D, 6.4A, 6.4B, 6.6A, 6.6B, 6.6C

Introduction

This unit bundles Student Expectations that address how the physical properties of matter can be used for classification and identification. Metals, nonmetals, and metalloids are classified based on their physical properties. Unknown substances can be identified by their density, and minerals are identified based on their physical properties.

Prior to this Unit

• Grade 3

  • 3.5A – Measure, test, and record physical properties of matter, including temperature, mass, magnetism, and the ability to sink or float.

• Grade 4

  • 4.5A – Measure, compare, and contrast physical properties of matter, including mass, volume, states (solid, liquid, gas), temperature, magnetism, and the ability to sink or float.

• Grade 5

  • 5.5A – Classify matter based on measurable, testable, and observable physical properties, including mass, magnetism, physical state (solid, liquid, and gas), relative density (sinking and floating using water as a reference point), solubility in water, and the ability to conduct or insulate thermal energy or electric energy.

• Grade 3, Mathematics

  • 3.7E – Determine liquid volume (capacity) or weight using appropriate units and tools.

• Grade 4, Mathematics

  • 4.4H – Solve with fluency one- and two-step problems involving multiplication and division, including interpreting remainders.

  • 4.5A – Represent multi-step problems involving the four operations with whole numbers using strip diagrams and equations with a letter standing for the unknown quantity.

  • 4.8C – Solve problems that deal with measurements of length, intervals of time, liquid volumes, mass, and money using addition, subtraction, multiplication, or division as appropriate.

• Grade 5, Mathematics

  • 5.3G – Solve for quotients of decimals to the hundredths, up to four-digit dividends and two-digit whole number divisors, using strategies and algorithms, including the standard algorithm.

  • 5.4B – Represent and solve multi-step problems involving the four operations with whole numbers using equations with a letter standing for the unknown quantity.

  • 5.4G – Use concrete objects and pictorial models to develop the formulas for the volume of a rectangular prism, including the special form for a cube(V = l x w x h, V = s x s x s, and V = Bh)

  • 5.4H – Represent and solve problems related to perimeter and/or area and related to volume.

  • 5.6A – Recognize a cube with side length of one unit as a unit cube having one cubic unit of volume and the volume of a three-dimensional figure as the number of unit cubes (n cubic units) needed to fill it with no gaps or overlaps if possible.

During this Unit

Students use scientific practices and a variety of tools to investigate the physical properties of matter. They use physical properties to compare metals, nonmetals, and metalloids. Students use the Periodic Table to identify the locations of metals, nonmetals, and metalloids for the purpose of seeing how substances with like properties are classified. Additionally, students calculate density to identify an unknown substance and test the physical properties of minerals. Students communicate and discuss their observations and record and organize data in their notebooks. Furthermore, students analyze and interpret information to construct reasonable explanations based on evidence from their investigations and communicate valid conclusions (supported by collected data). Students continue to demonstrate safe practices as outlined in the Texas Education Agency-approved safety standards and consider environmentally appropriate and ethical practices with resources during investigations.

Note: Students will be allowed the use of calculators on the Grade 8 Science STAAR Assessment.

In Grade 6 Mathematics, students are concurrently learning to divide positive rational numbers to include decimal dividends and divisors (6.3E). Since students have not yet mastered solving for quotients, including dividends and divisors with decimals, science teachers are encouraged to work closely with the mathematics teachers to ensure the same language and processes are being taught in both content areas with regards to calculating density. Therefore, teachers may want to consider restricting the numbers and mathematics to solving division problems with decimals, in which the four-digit dividend (mass) may be a decimal and the two-digit divisor (volume) is a whole number with a quotient (density) limited to the hundredths (5.3G), or allow students to use calculators during this unit. If restricting numbers is implemented, it is recommended to revisit calculating density later in the year to measure the density of objects and hold students accountable for solving for quotients, including dividends and divisors with decimals (6.3E).

After this Unit

In Grade 8, students will study the physical and chemical properties of matter and how they are related to the arrangement of the Periodic Table.