Using Dissolving to Identify Substances

Learning Resource Type

Classroom Resource

Subject Area

Science

Grade(s)

5

Overview

In this lesson, students will be able to plan and carry out an investigation to compare the solubility of different substances and develop and explain a particle-level model to describe the process of dissolving. Students will also be able to explain that substances dissolve in different amounts because of the molecules they are made from. Students are given labeled samples of salt and sugar. They are also given unknown samples marked A, B, and C. One is salt, one is sugar, and the other is alum, which looks like it could be either salt or sugar. Students first use a dissolving test to see how salt and sugar dissolve in water. Students then run the same dissolving test on substances A, B, and C; identify the salt and sugar; and conclude that the other substance must be something different. Students then see an animation to help explain that the substances are made of different atoms and molecules, so they dissolve differently.

Science (2015) Grade(s): 5

SC15.5.3

Examine matter through observations and measurements to identify materials (e.g., powders, metals, minerals, liquids) based on their properties (e.g., color, hardness, reflectivity, electrical conductivity, thermal conductivity, response to magnetic forces, solubility, density).

UP:SC15.5.3

Vocabulary

  • color
  • hardness
  • reflectivity
  • electrical conductivity
  • thermal conductivity
  • response to magnetic forces
  • solubility
  • density
  • measurement (quantitative and qualitative)
  • data
  • observable properties
  • standard units
  • conductors
  • nonconductors
  • magnetic
  • nonmagnetic

Knowledge

Students know:
  • Materials have different properties-color, hardness, reflectivity, electrical conductivity thermal conductivity, solubility, and density.
  • Measurements of a variety of properties can be used to identify materials.
  • Measurements should be made in standard units (e.g., grams & liters).

Skills

Students are able to:
  • Identify the phenomenon through observations about materials, including color, hardness, reflectivity, electrical conductivity, thermal conductivity, response to magnetic forces, and solubility.
  • Identify the evidence and collect data about the observed objects in standard units (e.g., grams, liters).
  • Collaboratively plan the investigation.
  • Identify materials based on their properties.

Understanding

Students understand that:
  • Standard units are used to measure and describe physical quantities of materials such as weight, time, temperature, and volume. These measurements will assist in the identification of the materials ( e.g. powders, metals, minerals, and liquids).

Scientific and Engineering Practices

Planning and Carrying out Investigations

Crosscutting Concepts

Scale, Proportion, and Quantity

CR Resource Type

Lesson/Unit Plan

Resource Provider

Other

License Type

CUSTOM

Resource Provider other

American Chemical Society
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