I have images for 117 of the 118 elements (missing astatine). A lot of these are chemistry-specific and are based on properties of the elements. How does this sound?
Hydrogen - a nebula filled with water, referencing hydrogen’s role in water and its presence in the universe. Also, it’s on fire because hydrogen is flammable.
Helium - a gas glowing bright reddish-pink, also the sun (named after the sun, helios).
Lithium - lightweight lithium batteries floating on and reacting with water.
Beryllium - a very toxic emerald (a type of beryl).
Boron - borosilicate glassware, the standard in labs.
Carbon - diamond.
Nitrogen - liquid nitrogen freezing a plant, making it brittle.
Oxygen - liquid oxygen on fire.
Fluorine - a pale yellowish-green gas, less so than chlorine. Fluorine + basically anything = massive fire, so this will get some good mental images.
Neon - a gas glowing bright reddish-orange. Not all neon signs are neon - only the ones that glow that distinct reddish-orange color are true neon signs. The other elements show different colors.
Sodium - A bright yellow flame and spectral line for sodium, and streetlamps, whose yellow color is from sodium. It’s not actually salt for me, surprisingly.
Magnesium - the bright, blindingly white flame that magnesium gives off when burned, known by every chemist as a property of this metal.
Aluminium - aluminium foil. What else?
Silicon - computer chip probably. I’ve also handled real silicon before, so I know what the element itself looks like - like a semi-shiny bluish-grey, brittle substance.
Phosphorus - the red material in matches - fire.
Sulfur - a stinky block of yellowish powder.
Chlorine - a greenish gas.
Argon - a gas glowing lilac-violet.
Potassium - bananas. Also a violet flame and somewhat explosive.
Calcium - bones and a human skeleton.
Scandium - Scandinavia, its namesake. Or as an alloy to strengthen aluminium alloys.
Titanium - a strong, yet light metal capable of seemingly everything, from space travel to pocket watches to medical implants. A true strong titan (get it, titanium?)
Vanadium - Mostly used in steel alloys - wrenches come to mind. Other than the element itself, I have nothing, and it tends to get confused with chromium for me, with only thing keeping them apart being the fact that vanadium is “less than” chromium by 1. (Vanadium is 23 and forms +5 ions maximum, chromium is 24 and forms +6 ions maximum.)
Chromium - chrome plating. Also color, as chroma = color in Greek. Chromium got this name from the many colored compounds it produces.
Manganese - the first one I have no clear image for. I thought of potassium permanganate, whose magnesium(VII) ions produce an unmistakable bright pinkish-purple color. Other than that, I’m drawing a blank. But apparently it plays a role in avoiding oxidation of steel (which is mostly iron), which makes up most of manganese’s commercial use. Also used in batteries.
Iron - rust. And traditional iron bar magnets.
Cobalt - blue glassware.
Nickel - a nickel, despite the fact that US nickels are 25% nickel and 75% copper.
Copper - a penny, despite the fact that US pennies only have a copper exterior around a zinc core.
Zinc - one of the few metals I’ve directly handled (it has a bit of a blue shine to it and is quite light), so I have an image for this one.
Gallium - a solid metal that melts in your hand. Seriously. Gallium’s melting point is so low that some chemists mold spoons out of gallium and ask an unsuspecting person to stir some tea and then the spoon disappears into the tea. It’s a favorite prank of chemists.
Germanium - camera lenses make use of germanium as it is transparent in infrared light, and also the country of Germany, where the element gets its name.
Arsenic - toxic, and I shouldn’t have to explain. For me, it might be confused with thallium.
Selenium - the moon (selene in Ancient Greek, the namesake of the element). Also redder glass. (Glass on its own tends to be yellow or green due to iron impurities. Selenium adds a red color to cancel it out.)
Bromine - a reddish-brown lake evaporating into an orange gas.
Krypton - a gas glowing white.
Rubidium - a ruby-reddish square, possible violent explosion when reacting to water. Reddish-violet-hot pink flames.
Strontium - reddish flames and fireworks - the element produces a brilliant red color when burned. I’ve seen it in real life.
Yttrium - the red color of computer screens, as that is made with the help of yttrium (with the help of europium as well, which also provides the blue). And near-infrared lasers.
Zirconium - cubic zirconia is used to fake diamonds. Not to be confused with carbon, which makes the real diamonds.
Niobium - Niobe, who in Greek mythology was the daughter of Tantalus (see tantalum). She lost her seven male children. She is the weeping mother.
Molybdenum - this one’s name actually means “lead” in Greek as the discoverer confused its ores with lead ores somehow. It’s another element whose main use is in steel (come on humans, can’t you be a bit more different in your element applications?)
Technetium - artificial. I’m not sure. It has its uses in nuclear medicine, so maybe this space is like a hole in the table that has been filled in artificially.
Ruthenium - Russia, after the Latin name - Ruthenia. I sometimes confuse rhodium and ruthenium every now and then, telling them apart by their atomic numbers.
Rhodium - a rose, the origin of the name, based on the color of one of its compounds. Rhodium is sometimes used in expensive jewelry, like a silvery-white wedding ring. It’s a precious metal.
Palladium - similar to rhodium, used in electronics and jewelry.
Silver - self-explanatory.
Cadmium - two things come to mind. Cadmium is used in nickel-cadmium batteries and formerly in yellow paint (until it was realized cadmium was too toxic for paint).
Indium - the color indigo, its namesake. It’s a remarkably soft metal that when bent, lets out a distinct “indium cry” much like tin.
Tin - a tin can.
Antimony - a metalloid used in the trioxide for flame retardants and proofing.
Tellurium - the earth giving off a garlic smell, referencing the namesake of tellurium (the earth) and its garlic smell when handled by humans.
Iodine - bluish-violet-black crystals of iodine, evaporating into a violet gas.
Xenon - a gas glowing bluish-white.
Caesium - a blue clock, ticking away (the ticking of a cesium atom defines the second). Very violent nature and explodes when water touches it. Bluish-violet flames.
Barium - a heavy area of green fire with images of intestinal x-rays.
Lanthanum - a metal used in massive quantities for automobile batteries. Its name means “to lie hidden” because it was hidden with its fourteen brothers (the lanthanoid series of elements) all with similar properties and difficult to separate out, much like trying to separate a mixture of all of the spices in your kitchen.
Cerium - bright mischmetal sparks, from a cerium alloy. It’s a well-known use of cerium and the first image that comes to mind, other than the round asteroid/dwarf planet Ceres.
Praseodymium “green twin” (after its yellowish-green oxide). Can be used to color glass yellow, also combined with neodymium in welder’s goggles.
Neodymium - “new twin”. Neodymium is used to make very strong magnets. Originally neodymium and praseodymium were thought to be the same element - didymium. They were separated out in 1885.
Promethium - luminous paint (could be confused with radium’s image), also the Greek figure Prometheus, who stole fire from the gods to give it to humans.
Samarium - nothing much comes to mind. Powerful magnets can be made with samarium, and they’re the second-most powerful known, only next to neodymium magnets. Also, the samarium(II) ion is a blood red color in an aqueous solution.
Europium - Europe. Obviously. Also gives red and blue colors to TVs and computer screens. And europium compounds are used in euro banknotes to avoid counterfeit.
Gadolinium - a metal that is magnetic when cold, but nonmagnetic when warmed up. It also gives TV and computers screens their green color. Other than that, that’s about it.
Terbium - also used to create the green color of TVs and computer screens, but on a larger scale than gadolinium. Really, at this point you get a lot of very, very similar elements in a row and it’s hard to come up with distinct mental images.
Dysprosium - usually nonmagnetic, but it can become magnetic only at very, very cold temperatures, one of the few things distinctive about it.
Holmium - produces the strongest magnetic fields of any element.
Erbium - colors jewelry and glass a pink color. Also used in optical fibers to create the internet. Without erbium, you wouldn’t be reading this right now.
Thulium - “the most useless element”. Other than X-rays and lasers, there’s almost nothing that uses this element. Named for Thule, a mythological northern place around Scandinavia or Iceland.
Ytterbium - currently holds the record for the most stable atomic clock created.
Lutetium - I have almost nothing. Lutetium’s only main use is for X-ray phosphors as one of its compounds is the densest known stable white material.
Hafnium - named for Copenhagen, so maybe a Danish flag? Or microprocessors, one of the few uses for hafnium that zirconium isn’t used in along with rocket nozzles.
Tantalum - a computer capacitor and resistor, as those are the main uses for tantalum. They’re used everywhere in electronics. Or the Greek figure Tantalus after whom the element was named, with the water and fruit forever out of his reach.
Tungsten - filament in light bulbs.
Rhenium - jet engines, which use most of the world’s rhenium production.
Osmium - an osmium pen. Typically labeled as an “iridium pen” due to historical reasons (they no longer contain iridium).
Iridium - an iridium pen. Or a meter-long bar made of a platinum-iridium alloy used to define the meter until 1960.
Platinum - not sure other than the metal itself.
Gold - an ingot of dense, solid gold.
Mercury - a lake of liquid mercury.
Thallium - a soft and very toxic metal (like chalk maybe) with disgusting green overtones to it - the name means “green shoot”.
Lead - toxic plumbing. I don’t know what else.
Bismuth - rainbow-colored crystals that grow like squares, the most spectacular of all the elements in this regard.
Polonium - a thin film of toxic metal on a disk for radiation testing. Or Poland.
Astatine - nothing. I have absolutely nothing. Nothing at all. Zero. Zilch. This element is a frustrating blank for me. I have something for every element but this one.
Radon - an eerie-colored (we don’t know the color) glowing toxic gas. Or a radon detector instrument.
Francium - France. That’s all I have. Unless an image of manipulating a few thousand atoms of francium counts because that’s all we’ve been able to do with it.
Radium - a radium watch with white luminescent radium paint.
Actinium - Has a distinct blue glow to it… and nothing really else.
Thorium - Thor’s hammer, referencing mythology.
Protactinium - nothing obvious, as there are no non-scientific uses of the element. A protractor comes to mind based on the similarity to the name, but that’s it.
Uranium - uranium glass, Uranus.
Neptunium - Neptune itself, or a trident for its symbol.
Plutonium - Pluto, nuclear bomb (not really associated with uranium for me).
Americium - an ionization smoke detector (which uses this element).
Curium - Marie Curie.
Berkelium - Berkeley, California, of which I have no clear image.
Californium - a bear, for the California bear.
Einsteinium - Albert Einstein.
Fermium - Enrico Fermi. Yeah, you’re going to be noticing a trend here.
Mendelevium - Dmitry Mendeleev.
Nobelium - Alfred Nobel.
Lawrencium - Ernest Lawrence.
Rutherfordium - Ernest Rutherford.
Dubnium - Named for Dubna, Russia, of which I have no clear image other than the colors green and blue for some reason.
Seaborgium - Glenn T. Seaborg.
Bohrium - Niels Bohr.
Hassium - Named for Hessen, a state of Germany. I have no clear image. There’s also the UNO card game, which for me references unniloctium (symbol: Uno), an older name for the element. There’s also a video of someone saying “Hassium. I know nothing about hassium. Should we make something up?” which I find hilarious at least.
Meitnerium - Lise Meitner.
Darmstadtium - A Nintendo DS. It’s named after the city of Darmstadt, Germany, of which I have no clear image, so I use the chemical symbol Ds instead.
Roentgenium - Wilhelm Röntgen.
Copernicium - Nicolaus Copernicus.
Nihonium - Japan.
Flerovium - Georgy Flyorov (Flerov).
Moscovium - Moscow, Russia.
Livermorium - Livermore, California (the namesake of the element). Initially it was actual liver.
Tennessine - Tennessee.
Oganesson - Yuri Oganessian.