monatomic
Having one atom
Monatomic describes a molecule or substance consisting of single atoms rather than atoms bonded together.
The noble gases—helium, neon, argon—are monatomic because they exist as individual atoms, not pairs or clusters.
Monatomic hydrogen is rare under normal conditions.
The term appears mainly in chemistry and physics.
Lightest noble gas
- neonInert illuminating element
- argonUnreactive element eighteen
- kryptonInert gas, atomic thirty-six
- xenonElement fifty-four, noble gas
radon · inert · unreactive · stable · nonreactive · colorless · odorless · gaseous
One in number
- loneExisting by itself
- isolatedSeparated from others
- unboundNot tied down
- discreteIndividually separate, unconnected
individual · solitary · separate · free · unattached · simplest · indivisible · elementary
helium
Lightest noble gas
xenon · radon · inert · unreactive · stable · nonreactive · colorless · odorless · gaseous · diffusion
single
One in number
discrete · individual · solitary · separate · free · unattached · simplest · indivisible · elementary
hydrogen
Simplest atomic element
- oxygenElement eight, colorless gas
- nitrogenElement seven, colorless gas
- chlorineHalogen disinfectant element
fluorine · bromine · iodine · sodium · potassium · mercury · gold · silver · platinum · vapor