HHeLiBeBCNOF: you can say it out loud (H-heli-beb-cnof) to learn,  or to remind yourself of, the first nine elements in the Periodic Table. They represent hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen and fluorine.

The next 11 elements can also be said out loud: nee-nam-gall-sips-clark-ca (NeNaMgAlSiPSClArKCa). The elements in question are: neon, sodium, magnesium, aluminium, silicon, phosphorus, sulfur, chlorine, argon, potassium, calcium. You might have noticed the new, official spelling of sulfur there. Here in England we have, officially, dropped the “ph” in the middle and replaced it with the letter “f”. It makes sulfur an element with 6 letters rather than 7.

Do these ways of pronouncing the first 20 elements in the Periodic Table count as mnemonics? They’re not like “Richard of York gave battle in vain” for the colours of the rainbow, or “I can pluck moles” for remembering the order of adult teeth (incisor, canine, premolar, molar). It’s just pronouncing the letters as words, which you can also do with the initial letters of the colours of the rainbow (ROYGBIV, or red, orange, yellow, green, blue, indigo, violet). I’ll continue to describe them as mnemonics here in the absence of any obvious alternative word.

I memorized the first 20 elements just in time for my Chemistry O Level exams a few decades ago. We weren’t sure whether we would have access to the Periodic Table during the exams themselves, so I learnt them just in case. As things turned out we each had a printed copy of the table along with our exam papers, so we didn’t have to memorize any of it, but, as you can see, the information is still there all these years later.

I haven’t needed this information professionally. Those Chemistry exams, taken when I was 15, were the end of any formal scientific study for me and many of my school-friends. I have encountered plenty of Trivia questions about chemical elements since then, including one of my favourites: what is the symbol for tungsten? The answer is W, which stands for wolfram, an alternative name for tungsten. Its atomic number is 74 and my mnemonics, based on learning the elements in numerical order, run out way before then.

A few years ago I learnt the next batch of elements, up to 35, using a few more awkward-sounding words. CaScTiVCrMn takes you from 20 to 25 (calcium, scandium, titanium, vanadium, chromium, manganese) and FeCoNiCuZn gets you from 26 to 30, with the names of more everyday materials: iron, cobalt, nickel, copper and zinc. Gaggy-Assie-Br (GaGeAsSeBr) takes you to 35 with gallium, germanium, arsenic, selenium and bromine. After that it all gets a little hazy for me and I can only identify selected elements and numbers.

Another favourite quiz question, mentioned on my Trivia Menu, is to name the nine elements whose symbols and English names do not share any of the same letters. I can remember all nine words along with their atomic numbers, four of which have already appeared above: 11 (Na, sodium), 19 (K, potassium), 26 (Fe, iron) and 74 (W, tungsten). To remind myself of the remaining elements I recall their atomic numbers (47, 51, 79, 80, 82) and know that they correspond with (respectively) Ag (silver), Sb (antimony), Au (gold), Hg (mercury), Pb (lead).

There are a few other familiar numbers dotted around the various groups and rows in the table. I know that 99 is einsteinium (Es), 109 is Meitnerium (Mt) and 117 is tennessine (Ts). The latter does not appear on the Periodic Table poster that used to hang up in our kitchen. I have just unfolded it to check, but didn’t need to. The poster is at least three years old, and tennessine was only named in 2016 (along with nihonium, moscovium, and oganesson, as noted in this piece).

At some point I might be able to recite the last 20 elements with the same confidence as the first 20. Is there anything as memorable as HHeLiBeBCNOF to help me? Perhaps this dynamic Periodic Table will help.