NaCl Lattices and Water
Lending Library: NaCl Lattices and Water (NC)
Teaching Points
There are several different chemical bonds found in nature. Ionic bonding represents the attraction of
cations (positively charged ions) to anions (negatively charged ions). There is a strong electrostatic
interaction between these oppositely charged ions, which forms a bond that requires the input of
energy to break. One consequence of this high level of electrostatic attraction is the high boiling point
of molecules with ionic bonds.
Ionic bonding commonly generates lattices, in which the components of that lattice alternate with each
other in three-dimensional space. Common table salt, NaCl, is an example of a lattice generated
through ionic bonding between sodium ions (positively charged) and chloride ions (negatively
charged). Sodium has a single electron in its valence shell while chloride has seven electrons in its
outer valence shell. An ionic bond occurs when one atom “steals” an electron from another atom and
in so doing, allows for each valence shell to be complete. Visualizing the repeating pattern found in
salt lattices is often challenging for students. Through the models in this collection, the crystal shape
of salt is easily seen and manipulated.
This collection also includes models of water, so that the concept of solubility can be explored. The
ionic bond between sodium and chloride is easily dissociated in water as water will interact readily with
the ions. Through the use of these models, a student can examine how many water molecules are
needed to dissolve a single NaCl ionic bond. The concept of saturation can also be discussed with
reference to the availability of water to interact with NaCl molecules.
Models in this Collection
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6 3x3x3 NaCl Lattices
2 Water Cups
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Documentation Included
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How do the models fit back in the suitcase?
NaCl Lattice© Science Activities Teacher Notes
Patterns in Crystal Structures Teacher Notes
Patterns in Crystal Structures Student Handout
Patterns in Crystal Structures Teacher Key
All instructional materials for classroom use are available for printing.
These materials, including instructional materials for the Water Kit©, are accessible online at:
http://www.3dmoleculardesigns.com/Teacher-Resources.htm
General Model Information
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CPK coloring:
Carbon
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Oxygen
Hydrogen
Ion coloring:
Sodium Ion
Chloride Ion
Model Details
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Each 3x3x3 NaCl Lattice contains:
o 27 atoms, each ion has 6 embedded magnets to simulate ionic bonding
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Each Water cup contains:
o 12 magnetic water molecules
o 1 sodium ion
o 1 chlorine ion
o 1 ethane core with 5 non-magnetic hydrogens
o 1 hydroxyl group
o 1 non-magnetic hydrogen with gray post
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