I am a transition metal with 25 electrons.
Answer Manganese (Mn)
A neutral atom has as many electrons as protons, so the atomic number is 25. Element 25 is manganese, a transition metal in group 7.
Element riddle solver
Type a chemistry riddle such as “I am a transition metal with 25 electrons”, or set the clues by hand. The solver narrows the 118 elements one clue at a time and explains every step.
Nihonium (Nh), element 113
Riddles of the kind set in chemistry homework, each solved from the periodic table.
Answer Manganese (Mn)
A neutral atom has as many electrons as protons, so the atomic number is 25. Element 25 is manganese, a transition metal in group 7.
Answer Nickel (Ni)
Group 10 holds nickel, palladium, platinum and darmstadtium. With the classroom shortcut, rounded atomic mass minus atomic number, nickel gives 59 − 28 = 31; its most common isotope, nickel-58, has 30.
Answer Moscovium (Mc)
Tennessine is element 117, so the answer has 117 − 2 = 115 protons. Element 115 is moscovium (Mc).
Answer Tellurium (Te)
Technetium has 43 electrons, and 43 + 9 = 52. Element 52 is tellurium.
Answer Tellurium (Te)
The element with 34 protons is selenium, in group 16 and period 4. Directly below it, in period 5, is tellurium.
Answer Nihonium (Nh)
A neutral atom has as many electrons as protons, so this is element 113, nihonium, a synthetic element named after Japan.
Answer Mercury (Hg)
80 electrons means atomic number 80, mercury. It melts at −38.8 °C, so it is a liquid at room temperature.
Answer Selenium (Se)
34 protons makes it selenium. Its atomic mass, 78.97, rounds to 79, and 79 − 34 = 45; its most common isotope, selenium-80, has 46.
Answer Xenon (Xe)
Xenon is the only noble gas in the list: oxygen and nitrogen are nonmetals and chlorine is a halogen.
Answer Copernicium (Cn)
Copernicium, element 112, has the largest listed mass (285), but it is made only in laboratories. Of the transition metals found in nature, mercury is the heaviest, at 200.59.
Answer Chlorine (Cl)
The halogens are group 17, and group 17 in period 3 is chlorine.
Answer Potassium (K)
The alkali metals are group 1 without hydrogen, and group 1 in period 4 is potassium.
Answer Iron (Fe)
26 protons makes it iron. Its atomic mass, 55.85, rounds to 56, and 56 − 26 = 30, which is also the neutron count of its most common isotope, iron-56.
Answer Carbon (C)
Silicon sits in group 14, period 3. Directly above it, in period 2, is carbon.
Homework riddles usually take the atomic mass from the periodic table, round it to a whole number and subtract the atomic number. For nickel that gives 59 − 28 = 31.
A real nickel atom most often has 30 neutrons, because its most common isotope is nickel-58. The solver accepts either reading and says which one the riddle used. Nickel (Ni)
In the element decoder the clues come to you: one hidden element, a few clues, and you name it. The daily puzzle is the same for everyone.