ALEX Classroom Resource

  

Temperature Changes in Dissolving

  Classroom Resource Information  

Title:

Temperature Changes in Dissolving

URL:

https://www.middleschoolchemistry.com/lessonplans/chapter5/lesson9

Content Source:

Other
American Chemical Society
Type: Lesson/Unit Plan

Overview:

In this lesson, students will feel the temperature change that occurs when a cold pack and a hot pack are activated. They will see that these temperature changes are due to a solid substance dissolving in water. Students will then compare the temperature changes that occur as four different solutes dissolve in water and classify these as either endothermic or exothermic. Students will be introduced to the concept that it takes energy to break bonds and energy is released when bonds are formed during the process of dissolving.

Students will be able to identify variables in an experiment to find out how much the temperature increases or decreases as each of the four solutes dissolves in water. Students will be able to correctly classify the process of dissolving as either exothermic or endothermic for each solute. Students will be able to explain that the temperature changes in dissolving are a result of the amount of energy released compared to the amount of energy used as “bonds” are formed and broken.

Content Standard(s):
Science
SC2015 (2015)
Grade: 8
Physical Science
4 ) Design and conduct an experiment to determine changes in particle motion, temperature, and state of a pure substance when thermal energy is added to or removed from a system.


NAEP Framework
NAEP Statement::
P12.5: Changes of state require a transfer of energy. Water has a very high specific heat, meaning it can absorb a large amount of energy while producing only small changes in temperature.

NAEP Statement::
P12.8: Atoms and molecules that compose matter are in constant motion (translational, rotational, or vibrational).

NAEP Statement::
P8.1: Properties of solids, liquids, and gases are explained by a model of matter that is composed of tiny particles in motion.

NAEP Statement::
P8.6a: Changes of state are explained by a model of matter composed of tiny particles that are in motion.

NAEP Statement::
P8.6b: When substances undergo changes of state, neither atoms nor molecules themselves are changed in structure.

NAEP Statement::
P8.6c: Mass is conserved when substances undergo changes of state.


Unpacked Content
Scientific And Engineering Practices:
Planning and Carrying out Investigations
Crosscutting Concepts: Systems and System Models
Disciplinary Core Idea: Matter and Its Interactions
Evidence Of Student Attainment:
Students:
  • Design an experiment to determine changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed from a system.
  • Conduct an experiment to determine changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed from a system.
Teacher Vocabulary:
  • Particle motion
  • Temperature
  • State [of Matter]
  • Pure substance
  • Thermal Energy
  • Kinetic Energy
  • System
Knowledge:
Students know:
  • Changes in particle motion of a pure substance occur when thermal energy is added to or removed from a system.
  • Changes in temperature of a pure substance occur when thermal energy is added to or removed from a system.
  • Changes in state of a pure substance occur when thermal energy is added to or removed from a system.
Skills:
Students are able to:
  • Identify the phenomena under investigation, which includes changes in particle motion, temperature, and state of a pure substance when thermal energy is added to or removed from a system.
  • Identify the purpose of the investigation, which includes determining changes in particle motion, temperature, and state of a pure substance when thermal energy is added to or removed from a system.
  • Develop a plan for the investigation individually or collaboratively.
  • Describe factors used in the investigation including appropriate units (if necessary), independent and dependent variables, controls and number of trials for each experimental condition.
  • Perform the investigation as prescribed by the plan.
  • Use data from the investigation to provide an causal account of the relationship between the addition of removal of thermal energy from a substance and the change in the average kinetic energy of the particles in a substance.
Understanding:
Students understand that:
  • Adding or removing thermal energy from a system causes changes in particle motion of a pure substance.
  • Adding or removing thermal energy from a system causes changes in temperature of a pure substance.
  • Adding or removing thermal energy from a system causes changes in state of a pure substance.
AMSTI Resources:
AMSTI Module:
Exploring the Properties of Matter

Alabama Alternate Achievement Standards
AAS Standard:
SCI.AAS.8.4- Recognize that changes in temperature can cause changes in the state of matter of a substance; recognize that these changes are a result of changes in particle motion.


Tags: bond, dissolve, endothermic, energy, exothermic, solutes, solutions, substances, temperature
License Type: Custom Permission Type
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Comments
  This resource provided by:  
Author: Stephanie Carver