Physics & Chemistry

The model visualizes the concentrations of H3O+ and OH- at different pH levels. It helps to address four common misconceptions on the pH of solution. It also provides the pH values of a collection of common items.

• Grades: 6-12, College general chemistry

• NGSS Standards: MS-PS1-2, HS-PS1-5

This model presents the differences in titrating a strong acid (HCl) and a weak acid (Acetic acid). Students are able to observe the changes in pH when titrating a strong/weak acid with NaOH solution. Students may also change the concentrations of acids and the titrant and observe the corresponding results.

• Grades: 6-12, College general chemistry

• NGSS Standards: MS-PS1-2, HS-PS1-5

This model presents the differences in titrating a strong base (NaOH) and a weak base (Ammonia). Students are able to observe the changes in pH when titrating a strong/weak base with a HCl solution. Students may also change the concentrations of bases and the titrant and then observe the corresponding results.

• Grades: 6-12, College general chemistry

• NGSS Standards: MS-PS1-2, HS-PS1-5

Carbonic acid (H2CO3), Bicarbonate ion (HCO3-), and carbonate ion (CO3 (2-))are three species of dissolved inorganic carbon (DIC) that coexist in water. In a closed system, assuming that no carbon leaves or enters the system, the proportions of these species are determined by many factors. This model presents the proportions of three DIC species at different pH levels, ranging from 0 to 14, holding other factors constant. This model may serve as the foundation for students to explore the phenomenon of ocean acidification.

• Grades: 6-12, College general chemistry

• NGSS Standards: MS-PS1-2, HS-PS1-5, HS-ESS3-6

This model represents the changes of state at the micro-particle level. By heating up and cooling down a set of particles, students can explore the fundamental features of three states. This model is particularly good for students to identify visual evidence for describing different states and the changes, and explore the relationships between particles’ kinetic energy and the space they may take.

• Grades: 6-8

• NGSS Standards: MS-PS1-4.

This model represents the changes of state at the micro-particle level. In this model, the states of matter are determined by three factors–kinetic motion, attraction and repulsion. By heating up and cooling down a set of particles, students can explore the fundamental features of three states. This model also allows students to explore the interplay between the attractive force and repulsive force. This model is particularly good for students to identify visual evidence for describing different states and the changes, as well as explore how the states of matter are influenced by intermolecular forces and the kinetic energy.

• Grades: 6-8:

• NGSS Standards: MS-PS1-4.

This model simulates the state changes of water. By heating up and cooling down the water molecules in the model, you add to and remove the kinetic energy from the molecules. Due to the intermolecular forces, these water molecules will then take more or less space. When they are cooled down enough, these molecules will form a crystalized structure, i.e.,ice. This model can be used to explore the states of water, the relationships between molecules’ kinetic energy and space they may take, and the unusual space changes in water when it freezes.

• Grades: 6-8

• NGSS Standards: MS-PS1-4.