A survey of 21 free online buffer calculators and apps found only 2 that correctly calculated pH under conditions where [H[superscript +]] and [OH[superscript -]] cannot be ignored in the ratio term of the Henderson-Hasselbalch equation. Traditional guidelines for when use of formal concentrations is acceptable were found to be flawed. For acidic…

PQcalc is an online calculator designed to support students in college-level science classes. Unlike a pocket calculator, PQcalc allows students to set up problems within the calculator just as one would on paper. This includes using proper units and naming quantities strategically in a way that helps finding the solution. Results of calculations…

Among computational methods, DFT (density functional theory) and TD-DFT (time-dependent DFT) are widely used in research to describe, "inter alia," the optical properties of transition metal complexes. Inorganic/physical chemistry courses for undergraduate students treat such methods, but quite often only from the theoretical point of…

A solid foundation of chemistry principles is only gained through a true comprehension of the material as opposed to pure memorization. One of the most fundamental concepts in chemistry is that of determining the amount of product formed in a chemical reaction when one of the reactants is limiting. To increase students' comprehension of this…

This technology report alerts upper-division undergraduate chemistry faculty and lecturers to the use of Texas Instruments emulators as virtual graphing calculators. These may be used in multimedia lectures to instruct students on the use of their graphing calculators to obtain solutions to complex chemical problems. (Contains 1 figure.)

We report on the contents and results for 360 students of a mathematics assessment administered at the start of the second-semester introductory chemistry course required for science and engineering majors at the University of Minnesota. This calculator-free, 20-question, 30-minute, multiple-choice, diagnostic quiz includes questions selected…

The velocity of sound in a gas depends on its temperature, molar mass, and [lambda] = C[subscript p]/C[subscript v], ratio (heat capacity at a constant pressure to heat capacity at constant volume). The [lambda] values for air, oxygen, nitrogen, argon, and carbon dioxide were determined by measuring the velocity of the sound through the gases at…

The use of Calculator-Based Laboratory (CBL) technology, the graphing calculator, and the cooling and heating of water to model the behavior of consecutive first-order reactions is presented, where B is the reactant, I is the intermediate, and P is the product for an in-class demonstration. The activity demonstrates the spontaneous and consecutive…

A method to provide students a vision of how they can write iteration programs on an inexpensive programmable pocket calculator, without requiring a PC or a graphing calculator is developed. Two iteration methods are used, successive-approximations and bisection methods.

Describes the desk top calculators now on the market, including manufacturers, prices, and functions performed. Provides a table of specifications for programmable desk calculators. (MLH)

Provides instructions for and examples of balancing chemical equations using a desktop calculator. (JN)

A combination of graphical thinking with chemical and physical theories in the classroom is encouraged by using the Calculator-Based Laboratory System (CBL) with a temperature sensor and graphing calculator. The theory of first-order kinetics is logically explained with the aid of the cooling or heating of the metal bead of the CBL's temperature…

Describes an adaptation of the chemistry of lightsticks to use the calculator-based laboratory (CBL) interface, a TI-82/83 graphing calculator, and an easily manufactured wooden block as the support system. (CCM)

Describes the different types of scientific calculators and explains how graphic calculators can apply to chemical problems. (Contains 19 references.) (YDS)

A demonstration, which shows that the graphing calculation can greatly supplement the computer and often eliminates the need for computers and science, is given. The graphic calculator is a handheld computer, more powerful than most sophisticated computer of 25 years ago.