MS-PS1-5

← MS-PS1-2

MS-PS1-6 →

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.

Clarification statement: Emphasis is on the law of conservation of matter and on physical models or drawings, including digital forms, that represent atoms.

Assessment boundary: Assessment does not include the use of atomic masses, balancing symbolic equations, or intermolecular forces.

Performance Level Descriptions

Every Regents exam question on MS-PS1-5 is written to match one of the performance level descriptions (PLDs) below.

Level 1: Given a model showing a chemical reaction, identify evidence that proves the total number of atoms is conserved.

Level 2: Given a model, describe how the total number of each type of atom does not change in a chemical reaction and/or that mass is conserved.

Level 3: 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.

Level 4: Develop and use a model (including balanced equations and/or atomic masses) to describe how the total number of each type of atom does not change in a chemical reaction and because of this, mass is conserved.

Resources

Examples and discussion of resources for the learning, teaching, and assessment of MS-PS1-5.

This section could be expanded upon. You can help out by adding to this section.

Grade 8 Science Test Questions

Released New York State Grade 8 science test questions that assess MS-PS1-5 are listed here by test and question cluster. Each link opens the question with its answer key.

• Investigating Chemical Reactions Q3
• The Chemistry of Propane Q51

NGSS Dimensions

Performance expectation MS-PS1-5 was developed using the following elements from the NRC document A Framework for K-12 Science Education:

Science and Engineering Practices

• Developing and Using Models
  • Develop a model to describe unobservable mechanisms.

Disciplinary Core Ideas

• PS1.B: Chemical Reactions
  • (NYSED) Substances react chemically in characteristic ways. When substances react, the atoms that make up the molecules rearrange, forming new substances with different properties.
  • The total number of atoms does not change in a chemical reaction and thus mass is conserved.

Crosscutting Concepts

• Energy and Matter
  • Matter is conserved because atoms are conserved in physical and chemical processes.

Connections to Other Standards

MS-PS1-5 connections to ELA, math, and other science standards as outlined by the NYS Education Department:

Page contributors: Conrad Richman, Caroline Leonard, Shirley Shameen

MS | MS. Chemical Reactions