![]() ![]() Then the boric acid reacts with one hydroxide ion to produce tetrahydroxy borate anion. The tetraborate anion reacts with water to produce boric acid and two hydroxide anions. In the first step, sodium tetraborate dissociates into sodium cations and tetraborate anions. The step-wise mechanism in Figure 2 shows how sodium tetraborate in water produces boric acid. These chemical intermediates help explain the step-wise mechanism for the formation of the borax cross-link detailed in Figure 2.) Figure 1: Borax cross-link within polyvinyl alcoholĬopyright © 2011 Cherelle Bishop, Colorado State University Typically, chemical intermediates are quite reactive. Figure 1 shows how the sodium tetraborate, the active ingredient in borax, facilitates the formation of tetrahydroxy borate through a boric acid intermediate (Note: A chemical intermediate is a reaction product of one or more steps in a step-wise reaction that is not a final product in the chemical reaction. ![]() Students make their different formulations of poly(vinyl alcohol) by adding different amounts of sodium tetraborate (saturated borax solution). Then they design new versions of the putty that satisfies one of two different requirement options: very stretchy or rigid enough to bounce well. Students synthesize polymeric materials and create two different formulations of imitation Silly Putty. Changing the ratios of polymer and sodium tetraborate solutions in your imitation Silly Putty will affect how it bounces, stretches and goos! Sodium tetraborate is an ionic molecule that acts as a linker between the long chains of the polymers (draw Figure 1 on the board). ![]() Today, we are going to follow in James Wright's footsteps and use poly (vinyl alcohol) and sodium tetraborate (borax) solutions to make a slimy polymer, resembling Silly Putty! Did you know that poly (vinyl alcohol), the main ingredient in Elmer's Glue, is a long chain of repeating ethyl alcohol monomers? You can think of these ethyl alcohol monomers -(CH 2-CHOH)- as long strands of spaghetti. Although his invention of was not found to have good practical uses, Silly Putty did find success as a children's toy in 1949! This began to hamper war production efforts, especially the manufacture of tires and boots. During World War II, Japan occupied many of the natural rubber manufacturing countries in the Far East and cut off supply to the US. Who has played with Silly Putty? The recipe for Silly Putty was created by James Wright of General Electric in an attempt to make a synthetic rubber compound. This activity is designed to follow the Everyday Polymers lesson. Imitation Silly Putty Worksheet Answers (pdf) Visit [ to print or download.Ī familiarity with polymeric materials, polymerization and cross-linking. International Technology and Engineering Educators Association - Technology Investigating or designing new systems or structures requires a detailed examination of the properties of different materials, the structures of different components, and connections of components to reveal its function and/or solve a problem. about the process of development and the design and performance of a proposed process or system) in multiple formats (including orally, graphically, textually, and mathematically).Īlignment agreement: Thanks for your feedback!Īttraction and repulsion between electric charges at the atomic scale explain the structure, properties, and transformations of matter, as well as the contact forces between material objects. This activity focuses on the following Three Dimensional Learning aspects of NGSS:Ĭommunicate scientific and technical information (e.g.
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