| CHEMICAL INTERACTIONS COURSE MATRIX |
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SYNOPSIS |
SCIENCE
CONCEPTS |
PROCESSES |
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6. |
Heat of Fusion (optional; 2 sessions)
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Students conduct experiments to determine the amount of heat needed to convert a mass of ice at 0°C to a mass of
liquid water at 0°C. |
• Heat of fusion is the energy needed to change a solid substance into
liquid.
• Heat of fusion does not change the kinetic energy of particles in a
substance.
• The heat of fusion for water is about 80 calories per gram.
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• Mix hot water, ice, and ice water to discover
heat of fusion.
• Calculate heat of fusion from data.
• Explain the apparent discrepancy in energy
transfer when hot water melts ice.
• Explain that heat of fusion is energy that
melts ice without changing the kinetic
energy of particles. |
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7. |
Phase Change (7–8 sessions) |
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Students experience three common phases (states) of
matter—solid, liquid, and gas—and investigate the
conditions that induce substances to change from one
phase to another.. |
• Matter exists on Earth in three common phases (states).
• Change of state is the result of change of energy in the particles in a
sample of matter.
• During phase change, particles do not change; relationships between
particles do change.
• Different substances change phase at different temperatures.
• The processes of phase change are evaporation, condensation,
melting, |
• Use ice, hot water, and flame to transfer
heat to and from substances to observe
phase change.
• Explain phase in terms of the relationship of
particles to one another in a substance.
• Discuss phase change in terms of kinetic
energy and energy transfer. |
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8. |
Solutions (6 sessions) |
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Students compare aqueous mixtures, one with a soluble
solid and one with an insoluble solid. They then dissolve
table salt and Epsom salts to determine saturation
and discover that different substances have different
solubilities. In the last part, students engage the concept of
concentration, the ratio of solute to solvent in a solution. |
• A solution is a mixture in which one substance dissolves in another.
• Dissolving occurs when one substance (solute) is reduced to particles
and is distributed uniformly throughout the particles of a second
substance (solvent).
• Dissolving involves both kinetic interactions (collisions) and attractive
forces (bonds).
• Concentration is the ratio of solute particles to solvent particles. |
• Use balances to compare densities of
solutions and to infer concentration.
• Explain the process of dissolving.
• Explain how to find the amount of solute
needed to saturate a volume of solvent.
• Describe the characteristics of a solution at
the particle level. |
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9. |
Reaction (7 sessions) |
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Students blow bubbles into limewater, observe the
precipitate, and move atom tiles (representations) to
simulate the rearrangement of atoms to form new
substances (particles). Students conduct two other
reactions—hydrochloric acid/baking soda and an antacid
neutralization reaction—and learn to balance chemical
equations. |
• Atoms are the fundamental particles of elements.
• A compound is a substance made of two or more elements.
• Atoms combine to make particles of substances: molecules
and iconic compounds.
• Molecules and ionic compounds are held together by attractive
forces called bonds.
• A chemical reaction is a process in which atoms of substances
(reactants) rearrange to form new substances (products). |
• Use chemical formulas and balanced
chemical equations to represent chemical
reactions.
• Conduct a neutralization reaction to
determine the effectiveness of an antacid.
• Explain chemical reaction as a process
in which atoms rearrange to form new
substances. |
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10. |
More Reactions (5 sessions) |
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Students conduct more chemical reactions, learning about
limiting factors and reactants in excess. They observe the
oxidation of iron (rusting) and confirm the concentration of
oxygen in air by assuming that oxygen is the limiting factor. |
• The quantities of reactants available at the start of a reaction
determine the quantities of products.
• The limiting factor is the reactant present in the lowest concentration.
• Rusting is a reaction between atmospheric oxygen and iron.
• Reactants that remain in their original form after a reaction has run to
completion were present in excess. |
• Measure the volume of gas produced in
a reaction to infer the concentrations of
reactants.
• Use water displacement to determine the
volume of oxygen consumed during the
oxidation of iron. |
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