B. Objects and substances can be classified by their physical and chemical properties. Mass is the amount of matter (or "stuff") in an object. Weight, on the other hand, is the measure of force of attraction (gravitational force) between an object and Earth.
The concepts of mass and weight are complicated and potentially confusing to elementary students. Hence, the more familiar term of "weight" is recommended for use to stand for both mass and weight in grades K-5. By grades 6-8, students are expected to understand the distinction between mass and weight, and use them appropriately.
Clarification for grades K-2: The use of the more familiar term ‘weight’ instead of the term “mass” is recommended for grades K-2.
Clarification for grades 3-5: In grade 3, introduce the term mass as compared to the term weight. In grade 4, investigate the concept of weight versus mass of objects. In grade 5, discuss why mass (not weight) is used to compare properties of solids, liquids and gases.
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Original Student Tutorial
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Virtual Manipulatives
Original Student Tutorials Science - Grades K-8
Learn to sequence a series of diagrams to create a model of a substance transitioning from a solid state to a liquid state in this interactive tutorial.
Student Resources
Original Student Tutorial
Learn to sequence a series of diagrams to create a model of a substance transitioning from a solid state to a liquid state in this interactive tutorial.
Type: Original Student Tutorial
Virtual Manipulatives
This simulation will allow you to heat, cool and compress atoms and molecules and watch as they change between solid, liquid and gas phase.
Ideas to investigate:
- Describe characteristics of three states of matter: solid, liquid and gas.
- Predict how varying the temperature or pressure changes the behavior of particles.
- Compare particles in the three different phases.
- Explain freezing and melting with molecular level detail.
- Recognize that different substances have different properties, including melting, freezing and boiling temperatures.
Type: Virtual Manipulative
Students will pump gas molecules to a box and see what happens as they change the volume, add or remove heat, change gravity, and more. Measure the temperature and pressure, and discover how the properties of the gas vary in relation to each other.
- Students can predict how changing a variable among pressure, volume, temperature and number influences other gas properties.
- Students can predict how changing temperature will affect the speed of molecules.
- Students can rank the speed of molecules in thermal equilibrium based on the relative masses of molecules.
Type: Virtual Manipulative
This virtual manipulative allows you to investigate various aspects of gases through virtual experimentation. From the site: Pump gas molecules to a box and see what happens as you change the volume, add or remove heat, change gravity, and more (open the box, change the molecular weight of the molecule). Measure the temperature and pressure, and discover how the properties of the gas vary in relation to each other.
Type: Virtual Manipulative
Parent Resources
Virtual Manipulatives
This simulation will allow you to heat, cool and compress atoms and molecules and watch as they change between solid, liquid and gas phase.
Ideas to investigate:
- Describe characteristics of three states of matter: solid, liquid and gas.
- Predict how varying the temperature or pressure changes the behavior of particles.
- Compare particles in the three different phases.
- Explain freezing and melting with molecular level detail.
- Recognize that different substances have different properties, including melting, freezing and boiling temperatures.
Type: Virtual Manipulative
Students will pump gas molecules to a box and see what happens as they change the volume, add or remove heat, change gravity, and more. Measure the temperature and pressure, and discover how the properties of the gas vary in relation to each other.
- Students can predict how changing a variable among pressure, volume, temperature and number influences other gas properties.
- Students can predict how changing temperature will affect the speed of molecules.
- Students can rank the speed of molecules in thermal equilibrium based on the relative masses of molecules.
Type: Virtual Manipulative
•Use pictures and proportional reasoning to explain changes in concentration
•Draw what happens at the molecular level when compounds dissolve in water
•Identify if a compound is a salt or sugar by macroscopic observations or microscopic representations.
•Explain how using combinations of solutes changes solution characteristics or not.
•Use observations to explain ways concentration of a solute can change.
•Describe ways the formula, macroscopic observations, or microscopic representations of a compound indicates if the bonding is ionic or covalent.
Type: Virtual Manipulative
This virtual manipulative allows you to investigate various aspects of gases through virtual experimentation. From the site: Pump gas molecules to a box and see what happens as you change the volume, add or remove heat, change gravity, and more (open the box, change the molecular weight of the molecule). Measure the temperature and pressure, and discover how the properties of the gas vary in relation to each other.
Type: Virtual Manipulative