If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.


Periodic Table


March 1, 2019 | A version of this story appeared in Volume 97, Issue 9


Letters to the editor

Left-step periodic table

Thank you for Libby Bent Weberg’s letter on the left-step periodic table (C&EN, Jan. 21, page 3). Many of her readers may be encountering this representation of the periodic table for the first time, as there has been a virtual blackout on alternative formats of the periodic table in current literature. Students of today have no idea that the standard periodic table featured in textbooks and charts is not, perhaps, the ultimate stage in the evolution of the table.

Chemical educators are known to complain that the left-step table is too confusing for students, when in actual fact, it is the old standard table that is the more confusing. To wit, the system of electronic configuration is perfectly congruent with the left-step table, making it much simpler to introduce the concept of orbital filling, which leads to periodicity in a natural and organic sequence.

Despite the work of Henry Bent and others, Charles Janet’s table still has had limited impact on the chemical consciousness. At Periodic Round Table we are also working to gain acceptance for the left-step, or as we prefer to call it, eight-period table (8PT). Perhaps this process will gain more favorable attention during this 150th anniversary year of the periodic table.

Gary Katz
Cabot, Vermont


The recent article on environmental microplastics (C&EN, Feb. 4, page 28) was very informative but neglected a significant reality. Note that marine zooplankters consume tiny phytoplankton and each other (nutritious) and, increasingly, bits of microplastic (nonnutritious). If too much plastic serves as a food source, zooplankton populations decline, smaller fishes follow suit, on up through marine food webs. End results would be severe. Further, note that baleen whales feed on the particulate organic soup in the oceans; too much plastic consumed leads to their malnutrition, too.

The situation is roughly akin to eating pancakes made of Styrofoam. Food for thought, no pun intended.

Robert Pellenbarg
Berlin, Maryland

Alex Scott’s article is very timely. Recently in an article by K. V. Venkatasubramanian, the presence of microplastics in Indian sea salts was disclosed (C&EN, Sept. 17, 2018, page 19). What we give to nature, nature multiplies and gives back to us. We sow a seed, but nature gives it back multifold. So there should be no surprise that when we give a plastic to the ocean, it gives back millions of micro- and nanoplastics.

Amrit P. Bindra
Brecksville, Ohio


This article has been sent to the following recipient:

Chemistry matters. Join us to get the news you need.