--- title: MS-PS1-5 Lesson Plans | Conservation of Atoms in Reactions description: "MS-PS1-5: Conservation of Atoms and Mass in Reactions Develop and use a model to describe how the total number of atoms does not change in a chemical reaction and thus mass is conserved." image: https://www.knowatom.com/hubfs/Right%20Image.png --- [![Teacher Login](https://no-cache.hubspot.com/cta/default/347944/f56bee57-133e-4975-8055-799f1f23588b.png)](https://cta-redirect.hubspot.com/cta/redirect/347944/f56bee57-133e-4975-8055-799f1f23588b) [Teacher Login](https://app.knowatom.com/signin) [![KnowAtom Logo](https://www.knowatom.com/hubfs/KnowAtom%20Logo.svg "KnowAtom Logo")](https://www.knowatom.com/) # MS-PS1-5: Conservation of Atoms and Mass in Reactions Develop and use a model to describe how the total number of atoms does not change in a chemical reaction and thus mass is conserved. [![Download a Sample Unit](https://no-cache.hubspot.com/cta/default/347944/20eee377-e175-48fe-a039-ae723137a2a6.png)](https://cta-redirect.hubspot.com/cta/redirect/347944/20eee377-e175-48fe-a039-ae723137a2a6) Science & Engineering Practices - [Asking questions and defining problems](https://www.knowatom.com/asking-questions-and-defining-problems) - [Developing and using models](https://www.knowatom.com/developing-and-using-models) - [Planning and carrying out investigations](https://www.knowatom.com/planning-and-carrying-out-investigations) - [Analyzing and interpreting data](https://www.knowatom.com/analyzing-and-interpreting-data) - [Using mathematics and computational thinking](https://www.knowatom.com/using-mathematics-and-computational-thinking) - [Constructing explanations and designing solutions](https://www.knowatom.com/constructing-explanations-and-designing-solutions) - [Engaging in argument from evidence](https://www.knowatom.com/engaging-in-argument-from-evidence) - [Obtaining evaluating and communicating information](https://www.knowatom.com/obtaining-evaluating-and-communicating-information) Disciplinary Core Ideas - [Chemical Reactions](https://www.knowatom.com/chemical-reactions) - [Conservation of Energy and Energy Transfer](https://www.knowatom.com/conservation-of-energy-and-energy-transfer) Crosscutting Concepts - [Patterns](https://www.knowatom.com/patterns) - [Energy and Matter](https://www.knowatom.com/energy-and-matter) - [Scale Proportion and Quantity](https://www.knowatom.com/scale-proportion-and-quantity) [![New call-to-action](https://no-cache.hubspot.com/cta/default/347944/b5a1446e-d782-4a5f-a019-0b3b98c8304f.png)](https://cta-redirect.hubspot.com/cta/redirect/347944/b5a1446e-d782-4a5f-a019-0b3b98c8304f) ## Browse MS-PS1-5 Lesson Plans Grade Ranges All K-2 3-5 6-8 [![](https://www.knowatom.com/hubfs/Screenshot%20(24).png) ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/thermal-energy-and-particle-motion) ## [Thermal Energy and Particle Motion In this unit, students are introduced to science and engineering by exploring several phenomena that relate to cooking. Students begin with an investigation into the structure of matter and how energy determines state of matter. This page is a high level look at key components of this lesson. ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/thermal-energy-and-particle-motion) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/thermal-energy-and-particle-motion) [![](https://www.knowatom.com/hubfs/Grade/Screenshot%20(28).png) ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/chemical-reactions) ## [Chemical Reactions In this unit, students focus on interactions between matter and energy. In this lesson, students figure out the endothermic and exothermic phenomenon of chemical hot and cold packs to analyze matter and energy in different kinds of chemical reactions. This page is a high-level extract of this lesson. ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/chemical-reactions) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/chemical-reactions) [![](https://www.knowatom.com/hubfs/Grade/Screenshot%20(32).png) ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/the-rock-cycle) ## [The Rock Cycle In this unit, students use what they know about the relationship between energy and matter to investigate phenomena of how energy powers the cycling of Earth materials. They begin with this lesson on modeling the Earth processes that form different kinds of rock. This page provides an overview of this lesson.  ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/the-rock-cycle) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/the-rock-cycle) [![](https://www.knowatom.com/hubfs/Grade/Screenshot%20(32).png) ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/mass-and-heat-transfer) ## [Mass and Heat Transfer In this unit, students explore phenomena of natural processes that cause Earth’s surface to change over time, analyzing how energy causes Earth’s matter to transform and cycle from one form to another. In this lesson, students investigate how Earth materials are continually being reshaped and reformed by multiple processes that are powered by energy from Earth’s hot interior and the sun. This page is a high-level extract of this lesson. ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/mass-and-heat-transfer) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/mass-and-heat-transfer) [![](https://www.knowatom.com/hubfs/Grade/Screenshot%20(32).png) ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/renewable-energy) ## [Renewable Energy In this unit, students explore the natural processes that cause Earth’s surface to change over time, analyzing how energy causes Earth’s matter to transform and cycle from one form to another. In this lesson, they trace phenomena of how energy is transferred in chemical reactions, which allows scientists to produce ethanol to use as an alternative energy source. This page showcases each component of this lesson.](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/renewable-energy) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/7th-grade-science/renewable-energy) [![](https://www.knowatom.com/hubfs/image1-Oct-09-2023-06-17-28-2489-AM.png) ](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/mass-and-motion) ## [Mass and Motion In this unit, students encounter phenomena related to matter and energy as they learn about how engineers design materials with specific properties to address a wide range of societal needs.This page provides an overview of one lesson. ](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/mass-and-motion) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/mass-and-motion) [![](https://www.knowatom.com/hubfs/image4-Oct-09-2023-06-17-26-8016-AM.png) ](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/chemical-reactions) ## [Chemical Reactions In this unit, students explore the relationship between matter and energy using the phenomenon of material properties to discover why certain materials are useful for a particular function. For this lesson, they focus on the role of energy in changing matter during a chemical reaction phenomena between two substances. This page is a high-level extract of this lesson. ](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/chemical-reactions) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/chemical-reactions) [![](https://www.knowatom.com/hubfs/image3-Oct-08-2023-06-40-27-7927-PM.png) ](https://www.knowatom.com/science-phenomena-videos/5th-grade-science/magnets-and-motors) ## [Magnets and Motors In this unit, students explore the science phenomenon of electric currents and electrical energy. In this lesson, students figure out energy transfers, electricity, and circuits in the context of an electromagnetic motor system. This page showcases each key section of this lesson.](https://www.knowatom.com/science-phenomena-videos/5th-grade-science/magnets-and-motors) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/5th-grade-science/magnets-and-motors) [![](https://www.knowatom.com/hubfs/image1-Oct-08-2023-07-35-59-3594-PM.png) ](https://www.knowatom.com/science-phenomena-videos/6th-grade-science/atoms) ## [Atoms In this unit, students build on their knowledge of energy by exploring the relationship between energy and matter. They begin by modeling the structure of atoms and how atoms come together to form all of the matter in the universe. This page showcases each section of this lesson.](https://www.knowatom.com/science-phenomena-videos/6th-grade-science/atoms) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/6th-grade-science/atoms) [![](https://www.knowatom.com/hubfs/image4-Oct-08-2023-07-36-35-4598-PM.png) ](https://www.knowatom.com/science-phenomena-videos/6th-grade-science/molecules) ## [Molecules In this unit, students explore the science phenomena of interactions between energy and matter, analyzing how matter can only change when enough energy is present. In this lesson, they investigate the structure of molecules, relating this structure to the matter’s properties. This page is a high-level extract of this lesson.](https://www.knowatom.com/science-phenomena-videos/6th-grade-science/molecules) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/6th-grade-science/molecules) [![](https://www.knowatom.com/hubfs/image3-Oct-08-2023-07-36-38-7863-PM.png) ](https://www.knowatom.com/science-phenomena-videos/6th-grade-science/chemical-reactions) ## [Chemical Reactions In this unit, students build on their knowledge of energy by exploring the relationship between energy and matter. In this lesson students conduct an investigation into the science phenomenon of how energy is transferred in an endothermic reaction. This page provides an overview of this lesson. ](https://www.knowatom.com/science-phenomena-videos/6th-grade-science/chemical-reactions) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/6th-grade-science/chemical-reactions) [![](https://www.knowatom.com/hubfs/image3-Nov-01-2023-09-53-23-1062-AM.png) ](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/the-rock-cycle) ## [The Rock Cycle In this unit, students use what they know about the relationship between energy and matter to investigate phenomena of how energy powers the cycling of Earth materials. They begin with this lesson on modeling the Earth processes that form different kinds of rock. This page provides an overview of this lesson. ](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/the-rock-cycle) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/the-rock-cycle) [![](https://www.knowatom.com/hubfs/image1-Nov-08-2023-01-43-57-6396-PM.png) ](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/renewable-energy) ## [Renewable Energy In this unit, students explore the natural processes that cause Earth’s surface to change over time, analyzing how energy causes Earth’s matter to transform and cycle from one form to another. In this lesson, they trace phenomena of how energy is transferred in chemical reactions, which allows scientists to produce ethanol to use as an alternative energy source. This page showcases each component of this lesson.](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/renewable-energy) [ VIEW LESSON ](https://www.knowatom.com/science-phenomena-videos/8th-grade-science/renewable-energy) Standards citation: NGSS Lead States. 2013. *Next Generation Science Standards: For States, By State*s. Washington, DC: The National Academies Press. 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