n
(physics) The only stable isotope of aluminium, ²⁷₁₃Al, having thirteen protons and fourteen neutrons
n
(physics) A rare stable isotope of argon, ³⁶₁₈Ar, having eighteen protons and eighteen neutrons; it amounts to about 0.3% of the element in nature
n
(physics) A rare stable isotope of argon, ³⁸₁₈Ar, having eighteen protons and twenty neutrons; it amounts to about 0.06% of the element in nature
n
(physics) The major stable isotope of argon, ⁴⁰₁₈Ar, having eighteen protons and twenty-two neutrons; it amounts to about 99.6% of the element in nature
n
(physics) The only stable isotope of beryllium, ⁹₄Be, having four protons and five neutrons
adj
(physics) Having the electron configuration of beryllium
n
(physics) A stable isotope, ¹⁰₅B, having five protons and five neutrons, that makes up about 20% of natural boron; it is a good absorber of slow neutrons and is used as a radiation shield in Geiger counters
n
(physics) A stable isotope, ¹¹₅B, having five protons and six neutrons, that makes up about 80% of natural boron.
n
A radioactive isotope of caesium, ¹³⁷₅₅Cr, having 55 protons and 82 neutrons and which is formed mainly as a fission product by nuclear fission.
n
(physics) The major stable isotope of calcium, ⁴⁰₂₀Ca, having twenty protons and twenty neutrons; it amounts to almost 97% of the element in nature
n
(physics) A minor stable isotope of calcium, ⁴²₂₀Ca, having twenty protons and twenty-two neutrons; it amounts to about 0.6% of the element in nature
n
(physics) A minor stable isotope of calcium, ⁴³₂₀Ca, having twenty protons and twenty-three neutrons; it amounts to about 0.1% of the element in nature
n
(physics) A minor stable isotope of calcium, ⁴⁴₂₀Ca, having twenty protons and twenty-four neutrons; it amounts to about 2% of the element in nature
n
(physics) A radioactive isotope of calcium, ⁴⁵₂₀Ca, having twenty protons and twenty-five neutrons, and a half-life of 162.6 days; it is used as a tracer in studying calcium metabolism. As it decays it undergoes transformation (nuclear transmutation) via electron emission, also called negative beta decay (β−-decay), into scandium.
n
(physics) A rare stable isotope of calcium, ⁴⁶₂₀Ca, having twenty protons and twenty-six neutrons; it amounts to only 0.004% of the element in nature
n
(physics) A naturally-occurring radioactive isotope of calcium, ⁴⁸₂₀Ca, having twenty protons and twenty-eight neutrons, and a half-life of 4.3x10¹⁹ years
n
(physics) the less common of the two stable isotopes of carbon, ¹³₆C, having six protons and seven neutrons
n
(physics) The major stable isotope of chlorine, ³⁵₁₇Cl, having seventeen protons and eighteen neutrons; it amounts to about 76% of the element in nature
n
(physics) A long-lived radioactive isotope of chlorine, ³⁶₁₇Cl, having seventeen protons and nineteen neutrons, and a half-life of 3x10⁵ years; it can be used to date samples of groundwater
n
(physics) The minor stable isotope of chlorine, ³⁷₁₇Cl, having seventeen protons and twenty neutrons; it amounts to about 24% of the element in nature
n
(physics) A minor stable isotope of chromium, ⁵³₂₄Cr, having 24 protons and 29 neutrons; it amounts to about 9% of the element in nature
n
(physics) A minor stable isotope of chromium, ⁵⁴₂₄Cr, having 24 protons and 30 neutrons; it amounts to about 2% of the element in nature
adj
(chemistry, rare) Containing or pertaining to trivalent curium.
n
A highly fissile transuranic chemical element (symbol Cm) with an atomic number of 96.
n
(physics) An artificial radioisotope of fluorine, ¹⁸₉F, having 9 protons and 9 neutrons, that is an important industrial source of positrons
n
(physics) The only stable isotope of fluorine, ¹⁹₉F; it has nine protons and ten neutrons
n
(uncountable) The second lightest chemical element (symbol He) with an atomic number of 2 and atomic weight of 4.002602, a colorless, odorless and inert noble gas.
n
(physics) The rare isotope of helium, ³₂He, that has a single neutron
n
The lightest chemical element (symbol H), with an atomic number of 1 and atomic weight of 1.00794.
n
(physics) The isotope of thorium ²³⁰₉₀Th
n
(physics) A minor stable isotope of iron, ⁵⁴₂₆Fe, having 26 protons and 28 neutrons; it amounts to about 6% of the element in nature
n
(physics) The major stable isotope of iron, ⁵⁶₂₆Fe, having 26 protons and 30 neutrons; it amounts to about 92% of the element in nature
n
(physics) A minor stable isotope of iron, ⁵⁷₂₆Fe, having 26 protons and 31 neutrons; it amounts to about 2% of the element in nature
n
(physics) A radioactive isotope, ⁸⁵₃₆Kr, having thirty-six protons and forty-nine neutrons
n
(chemistry, physics) the progressive decrease in the radii of atoms of the lanthanide elements as the atomic number increases; evident in various physical properties of the elements and their compounds
n
(physics) A stable isotope ⁶₃Li, having three protons and three neutrons, that makes up about 7% of natural lithium; it is used in the nuclear industry.
n
(physics) A stable isotope, ⁷₃Li, having three protons and four neutrons, that makes up about 93% of natural lithium.
n
(physics) The major stable isotope of magnesium, ²⁴₁₂Mg, having twelve protons and twelve neutrons; it amounts to about 79% of the element in nature
n
(physics) A minor stable isotope of magnesium, ²⁵₁₂Mg, having twelve protons and thirteen neutrons; it amounts to about 10% of the element in nature
n
(physics) A minor stable isotope of magnesium, ²⁶₁₂Mg, having twelve protons and fourteen neutrons; it amounts to about 11% of the element in nature
n
(physics) The only stable isotope of manganese, ⁵⁵₂₅Mn, having 25 protons and 30 neutrons
n
(countable) A single atom of this element.
n
(physics) The major stable isotope of neon, ²⁰₁₀Ne, having ten protons and ten neutrons; it amounts to over 90% of the element in nature
n
(physics) A rare stable isotope of neon, ²¹₁₀Ne, having ten protons and eleven neutrons; it amounts to less than 0.3% of the element in nature
n
(physics) A minor stable isotope of neon, ²²₁₀Ne, having ten protons and twelve neutrons; it amounts to about 9% of the element in nature
n
(physics) A radioactive isotope of nitrogen, ¹³₇N, having seven protons and six neutrons, and a half-life of less than ten minutes; it is used in positron emission tomography
n
(physics) A stable isotope of nitrogen, ¹⁴₇N, having seven protons and seven neutrons; it accounts for over 99% of the natural element.
n
(physics) A stable isotope of nitrogen, ¹⁵₇N, having seven protons and eight neutrons; it accounts for less than 0.4% of the natural element; it is used in nuclear magnetic resonance spectroscopy
n
(physics) The major stable isotope of oxygen, ¹⁶₈O, having eight protons and eight neutrons; it amounts to over 99% of the element in nature
n
(physics) A minor stable isotope of oxygen, ¹⁸₈O, having eight protons and ten neutrons; it amounts to about 0.2% of the element in nature
n
(physics) The only stable isotope of phosphorus, ³¹₁₅P, having fifteen protons and sixteen neutrons
n
(physics) The major stable isotope of potassium, ³⁹₁₉K, having nineteen protons and twenty neutrons; it amounts to over 93% of the element in nature
n
An atom of this isotope.
n
(physics, rare) A highly unstable synthetic isotope of the element hydrogen, ⁴₁H, having one proton and three neutrons.
n
(physics) The radioactive isotope of actinium, ²²⁷₈₉Ac, having a half-life of 21.7 years
n
(physics) the only stable isotope of scandium, ⁴⁵₂₁Sc, having twenty-one protons and twenty-four neutrons
n
(physics) The major stable isotope of silicon, ²⁸₁₄Si, having fourteen protons and fourteen neutrons; it amounts to over 92% of the element in nature
n
(physics) A minor stable isotope of silicon, ²⁹₁₄Si, having fourteen protons and fifteen neutrons; it amounts to almost 5% of the element in nature
n
(physics) A minor stable isotope of silicon, ³⁰₁₄Si, having fourteen protons and sixteen neutrons; it amounts to 3% of the element in nature
n
(physics) The major stable isotope of sulfur, ³²₁₆S, having sixteen protons and sixteen neutrons; it amounts to 95% of the element in nature
n
(physics) A minor stable isotope of sulfur, ³³₁₆S, having sixteen protons and seventeen neutrons; it amounts to less than 1% of the element in nature
n
(physics) A minor stable isotope of sulfur, ³⁴₁₆S, having sixteen protons and eighteen neutrons; it amounts to about 4% of the element in nature
n
(physics) A radioactive isotope of sulfur, ³⁵₁₆S, having sixteen protons and nineteen neutrons, and a half-life of about 87 days; it is used as a tracer
n
(physics) A minor stable isotope of sulfur, ³⁶₁₆S, having sixteen protons and twenty neutrons; it amounts to only 0.01% of the element in nature
n
Alternative form of super-heavy water [(chemistry) Water containing tritium instead of normal hydrogen (symbol T₂O).]
n
The radioactive isotope of tellurium ¹²⁸₅₂Te
n
(physics) A radioactive isotope of thorium, ²²⁸₉₀Th, having a half-life of 1.4 x 10¹⁰ years; it occurs naturally, and is a source of nuclear energy
n
(physics) The isotope of radon ²²⁰₈₆Rn
n
(physics) A minor stable isotope of titanium, ⁴⁶₂₂Ti, having twenty-two protons and twenty-four neutrons; it amounts to about 8% of the element in nature
n
(physics) A minor stable isotope of titanium, ⁴⁷₂₂Ti, having twenty-two protons and twenty-five neutrons; it amounts to about 7% of the element in nature.
n
(physics) The major stable isotope of titanium, ⁴⁸₂₂Ti, having twenty-two protons and twenty-six neutrons; it amounts to about 74% of the element in nature
n
(physics) A minor stable isotope of titanium, ⁴⁹₂₂Ti, having twenty-two protons and twenty-seven neutrons; it amounts to about 5% of the element in nature
n
(physics) A minor stable isotope of titanium, ⁵⁰₂₂Ti, having twenty-two protons and twenty-eight neutrons; it amounts to about 5% of the element in nature
n
Any element lying beyond uranium in the periodic table.
n
(physics) A fissile isotope of uranium, used for energy generation and in atomic weapons, containing one hundred and forty-three neutrons. It has a half-life of 7·038×10⁸ years; it decays into thorium-231 and ultimately lead.
n
(physics) The naturally-occurring radioactive isotope of vanadium, ⁵⁰₂₃V, having twenty-three protons and twenty-seven neutrons; its half-life is 1.5 x 10¹⁷ years
n
(physics) The only stable isotope of vanadium, ⁵¹₂₃V, having twenty-three protons and twenty-eight neutrons
Note: Concept clusters like the one above are an experimental OneLook
feature. We've grouped words and phrases into thousands of clusters
based on a statistical analysis of how they are used in writing. Some
of the words and concepts may be vulgar or offensive. The names of the
clusters were written automatically and may not precisely describe
every word within the cluster; furthermore, the clusters may be
missing some entries that you'd normally associate with their
names. Click on a word to look it up on OneLook.
Our daily word games Threepeat and Compound Your Joy are going strong. Bookmark and enjoy!
Today's secret word is 7 letters and means "No longer existing; died out." Can you find it?