In part 1 published in the April 2017 issue, the molecular structures of the photochromic dyes used in eyeglass lenses were discussed. In part 2, the engineering and chemical design of the lenses will be highlighted. The student questions will focus on kinetics and experimental design.
If a chemist has never been in a lab accident, they have been lucky. Of course, luck is more likely to come to those whose mentors have learned from bad experiences and to those who have taken preventive measures seriously.
Health Canada issued an advisory this past summer, suggesting that exposure to boron substances be reduced as much as possible from all sources.
The Merriam-Webster dictionary defines photochromic(1) as: “capable of changing color on exposure to radiant energy (as light), e.g., photochromic glass”. Photochromic eyeglass lenses were introduced in 1966, and photochromic plastic lenses....
The basic idea is that in any Lewis structure, all atoms (except hydrogen), whether single, double or triple bonded require eight valence electrons (VEs). Any valence electrons left over will have to be incorporated as lone pairs around the central atom. So all one has to do is count the number of valence electrons in the structure, subtract the number of valence electrons involved in a bonded atom, eight for all bonded atoms, according to the octet rule, except for H, which requires two.
Students often struggle with the difference between a solution that is buffered and one that is not.
We began to use individual tablets of over-the-counter (OTC) consumer products as samples for some introductory analytical chemistry experiments in 2006.
Fentanyl is a synthetic, lipophilic phenylpiperidine derivative with both analgesic (painkiller) and anesthetic (causes reversible loss of consciousness) properties.....
Why is the heavy metal element gadolinium utilized in MRI scanning? Is there any chemistry involved? Yes. Read on.
Equilibrium is a challenging topic for high school chemistry students to understand. This year I decided to tackle the conceptual understanding of equilibrium first with three different analogies and a Process Oriented Guided Inquiry Learning (POGIL) activity before even mentioning the words "equilibrium expression".