The students formulate hypotheses for the chemical process that makes the hot and cold packets from segment A. Our host explains the difference between exothermic and endothermic reactions, and our students explore the concept of specific heat capacity by predicting whether ice cubes will melt faster when placed on metal or plastic.
The students formulate hypotheses for the chemical process that makes the hot and cold packets from segment A. Our host explains exothermic and endothermic reactions, and our students predict whether ice cubes will melt faster when placed on metal or plastic.
Premiere Date: August 15, 2016 | Runtime: 00:10:12
Defining the system under study—specifying its boundaries and making explicit a model of that system—provides tools for understanding and testing ideas that are applicable throughout science and engineering.
Observed patterns of forms and events guide organization and classification, and they prompt questions about relationships and the factors that influence them.
Energy and Matter
Flows, cycles, and conservation. Tracking fluxes of energy and matter into, out of, and within systems helps one understand the systems’ possibilities and limitations.
Stability and Change
For natural and built systems alike, conditions of stability and determinants of rates of change or evolution of a system are critical elements of study.
Science & Engineering Practices
Asking Questions and Defining Problems
Students at any grade level should be able to ask questions of each other about the texts they read, the features of the phenomena they observe, and the conclusions they draw from their models or scientific investigations. For engineering, they should ask questions to define the problem to be solved and to elicit ideas that lead to the constraints and specifications for its solution. (NRC Framework 2012, p. 56)
Planning and Carrying Out Investigations
Students should have opportunities to plan and carry out several different kinds of investigations during their K-12 years. At all levels, they should engage in investigations that range from those structured by the teacher—in order to expose an issue or question that they would be unlikely to explore on their own (e.g., measuring specific properties of materials)— to those that emerge from students’ own questions. (NRC Framework, 2012, p. 61)
absolute zero - the temperature at which all molecular motion stops and entropy is zero.
calorimetry - a method of measuring the quantity of heat transferred in a process.
chemical thermodynamics - the study of energy changes that accompany chemical reactions or physical changes in the state of matter; also known as thermochemistry.
endothermic - describes a process that takes in or absorbs energy from its surroundings.
enthalpy - a thermodynamic quantity equivalent to the total heat content of a system.
entropy - the measurement of energy dispersal.
exothermic - describes a process that produces or gives off energy to its surroundings.
first law of thermondynamics - the amount of energy in the universe is a constant. Energy can be transferred from one substance to another or transformed into other forms of energy, but it cannot be created or destroyed.
heat - the transfer of energy from a warmer object to a cooler object; also known as thermal energy.
joule - the SI unit of measure for energy, abbreviated J.
second law of thermodynamics - energy always disperses from a more usable form of energy to a less usable form.
specific heat capacity - the heat needed to raise the temperature of one gram of a substance by one degree Celcius.
surroundings - everything around the system, i.e. air, water, packaging, etc...
system - the chemical reaction or physical process being monitored.
temperature - a measurement of the average kinetic energy or molecular movement in an object or system.
thermal conductivity - a measure of the ability of a material to transfer heat.
third law of thermodynamics - the entropy of a system at absolute zero is zero.
Georgia Standards of Excellence
SC2Obtain, evaluate, and communicate information about the chemical and physical properties of matter resulting from the ability of atoms to form bonds.
SC2.gDevelop a model to illustrate the release or absorption of energy (endothermic or exothermic) from a chemical reaction system depends upon the changes in total bond energy.
SC3Obtain, evaluate, and communicate information about how the Law of Conservation of Matter is used to determine chemical composition in compounds and chemical reactions.
SC3.bPlan and carry out investigations to determine that a new chemical has formed by identifying indicators of a chemical reaction (specifically precipitate formation, gas evolution, color change, water production, and changes in energy to the system should be investigated).
SC5Obtain, evaluate, and communicate information about the Kinetic Molecular Theory to model atomic and molecular motion in chemical and physical processes.
SC5.aPlan and carry out an investigation to calculate the amount of heat absorbed or released by chemical or physical processes. (Clarification statement: Calculation of the enthalpy, heat change, and Hess’s Law are addressed in this element.)
SPS7Obtain, evaluate, and communicate information to explain transformations and flow of energy within a system.
SPS7.cAnalyze and interpret specific heat data to justify the selection of a material for a practical application (e.g., insulators and cooking vessels).
Request Teacher Toolkit
The Chemistry Matters teacher toolkit provides instructions and answer keys for labs, experiments, and assignments for all 12 units of study. GPB offers the teacher toolkit at no cost to Georgia educators. Complete and submit this form to request the teacher toolkit. You only need to submit this form one time to get materials for all 12 units of study.