Listening to pH

Abstract

We developed a simple device to teach the concept of pH to visually impaired people through an experimental approach. An interface between a glass electrode and an open-source electronics platform based on easy-to-use hardware and software (Arduino Uno) was designed using an operational amplifier of ultralow input current. A headphone connected to digital output from Arduino Uno was employed to convert the electrical signals from pH to sound frequency. Using an audio file that emits sound frequencies, visually impaired students were trained to associate specific frequencies with pH values. There is a direct relationship between the logarithm of sound frequency from a given musical note and a pH value, which can be used to train students with low vision who would otherwise have difficulty observing pH values from visual indications. Sound frequency signals of 131−659 Hz that correspond to the piano musical scale of C 3 , which is one octave below middle C (small octave or the "Do" note in solfege), to E 5 , one octave above middle E (two-lined octave or "Mi" note in solfege), were used to obtain sounds for the pH scale. Each musical note from these scales corresponded to one pH value with precision of 0.5 unit. This proposed method can be easily implemented in a laboratory with a relatively low cost.

Teaching Chemistry with Arduino Experiments in a Mixed Virtual-Physical Learning Environment

“…Arduino and other similar microcontrollers have already been used in various educational Chemistry applications as there is a wide variety of sensors which can be used, that are not expensive and produce highly accurate and reliable measurements (Pino et al, 2019). Arduino technology has been exploited for the construction of inexpensive Chemistry measuring devices such as pH meters and thermometers (Kubínová & Šlégr, 2015) that can even be used for students with visual impairment (Costa & Fernandes, 2019;Soong et al, 2018). Teachers can use these devices, exploiting a projector, an IB (Walkowiak & Nehring, 2016), or an LCD display (Pető, 2020) in order to monitor measurements.…”

Use of open source monitoring hardware to improve the production of MOFs: using STA-16(Ni) as a case study

“…Bespoke apparatus offers many advantages over commercial offerings—with flexibility, cost and ownership being key. A growing number of reports have demonstrated the use of these types of apparatus in education 1 , 2 , notably the ability to produce systems for students with disabilities 3 , 4 . Several reports have also demonstrated how such equipment can be used outside the teaching laboratories with the development of potentiometric detection 5 , scanning electrochemical microscopes 6 and electrochemical pre-treatment apparatus 7 all using inexpensive and open source hardware solutions.…”

Visualization without Vision – How Blind and Visually Impaired Students and Researchers Engage with Molecular Structures

“…Examples of other methods that utilize (or have the potential to utilize) audio include NavMol 2.0 (Fartaria et al, 2013), a software program that utilizes voice synthesizers and time clock polar coordinates to assist BVI individuals interpret and edit molecular structures, and polyfill solutions (Sorge, 2016) that take inaccessible bitmap images of molecules and convert them to scalable vector graphics, which are navigable via audio. Costa and Fernandes developed a simple device that can assist BVI individuals associate specific frequencies of sound with pH values (Costa & Fernandes, 2019). Despite these advances, many other challenges remain in creating technologies that rival tactile methods (Renier et al, 2010).…”