Give the atomic mass.
(2 d.p)
1.01
Hydrogen is the lightest element and consists of three isotopes - protium, deuterium, and tritium.
Give the atomic mass.
(2 d.p)
1.01
The atomic mass in atomic mass units (amu) considers the different naturally-occurring, stable isotopes of an element, such as the three isotopes of hydrogen.
Give the atomic mass.
(2 d.p)
4.00
Helium-4 is the most abundant and stable isotope of helium.
Give the atomic mass.
(2 d.p)
4.00
Helium-4 makes up 99.9999% of helium’s natural abundance.
Give the atomic mass.
(2 d.p)
6.94
Lithium is a light and soft metal and has two stable isotopes - lithium-6 and lithium-7.
Give the atomic mass.
(2 d.p)
6.94
The atomic mass accounts for the isotopic composition, in which lithium-7 makes up the overwhelming majority of lithium’s natural abundance.
Give the atomic mass.
(2 d.p)
9.01
Beryllium is a relatively rare element and has a high melting point.
Give the atomic mass.
(2 d.p)
9.01
Beryllium has only one stable isotope, beryllium-9.
Give the atomic mass.
(2 d.p)
10.81
Boron is a metalloid and plays a role in various industrial applications.
Give the atomic mass.
(2 d.p)
10.81
The atomic mass accounts for the isotopic composition of boron, of which its two key isotopes are B-10 and B-11.
Give the atomic mass.
(2 d.p)
12.01
Carbon’s atomic mass includes the average mass contributions of its isotopes, such as carbon-12 and carbon-13.
Give the atomic mass.
(2 d.p)
12.01
The atomic mass accounts for the isotopic composition of carbon, of which it has three isotopes C-12, C-13, and C-14.
Give the atomic mass.
(2 d.p)
14.01
Nitrogen makes up a significant portion of the Earth’s atmosphere in its diatomic gas form.
Give the atomic mass.
(2 d.p)
14.01
The atomic mass considers the different isotopes of nitrogen, of which it has two, N-14 and N-15.
Give the atomic mass.
(2 d.p)
16.00
Oxygen is a vital element for sustaining life and is abundant in the Earth’s crust.
Give the atomic mass.
(2 d.p)
16.00
The atomic mass accounts for the isotopic composition of oxygen, in which its three are O-16, O-17, and O-18.
Give the atomic mass.
(2 d.p)
19.00
Fluorine is a highly reactive and toxic halogen element.
Give the atomic mass.
(2 d.p)
19.00
The atomic mass considers the one stable isotope of fluorine, F-19.
Give the atomic mass.
(2 d.p)
22.99
Sodium is a highly reactive alkali metal commonly found in salts.
Give the atomic mass.
(2 d.p)
22.99
The atomic mass accounts for the isotopic composition of sodium, of which its key stable one is Na-23.
Give the atomic mass.
(2 d.p)
24.31
Magnesium is a lightweight and versatile metal used in various industries.
Give the atomic mass.
(2 d.p)
24.31
The atomic mass considers the three different isotopes of magnesium, Mg-24, Mg-25, and Mg-26.
Give the atomic mass.
(2 d.p)
26.98
Aluminium is a lightweight and malleable metal commonly used in various industries.
Give the atomic mass.
(2 d.p)
26.98
Aluminium is the most abundant metal in the Earth’s crust.
Give the atomic mass.
(2 d.p)
28.09
Silicon is a crucial element in the semiconductor industry due to its properties.
Give the atomic mass.
(2 d.p)
28.09
Silicon is widely used in electronic devices and solar panels.
Give the atomic mass.
(2 d.p)
30.97
Phosphorus is an essential nutrient for plants and animals.
Give the atomic mass.
(2 d.p)
30.97
Phosphorus plays a crucial role in various biological processes.
Give the atomic mass.
(2 d.p)
32.06
Sulphur is a nonmetallic element commonly used in the production of sulfuric acid.
Give the atomic mass.
(2 d.p)
32.06
Sulphur is known for its distinct smell and is present in various minerals.
Give the atomic mass.
(2 d.p)
35.45
Chlorine is a highly reactive element and a crucial component in disinfectants.
Give the atomic mass.
(2 d.p)
35.45
Chlorine is commonly used in water treatment and as a bleaching agent.
Give the atomic mass.
(2 d.p)
39.95
Argon is an inert gas commonly used in lightbulbs and welding.
Give the atomic mass.
(2 d.p)
39.95
Argon has three isotopes, with Ar-40 being by far the most abundant.
Give the atomic mass.
(2 d.p)
39.10
Potassium is an essential nutrient for plants and animals, and also plays a role in nerve function.
Give the atomic mass.
(2 d.p)
39.10
Potassium has three naturally-occurring isotopes, of which the most abundant is K-39.
Give the atomic mass.
(2 d.p)
40.08
Calcium is a vital mineral for the formation and maintenance of healthy bones and teeth.
Give the atomic mass.
(2 d.p)
40.08
Calcium is essential for muscle contractions and blood clotting.
Give the atomic mass.
(2 d.p)
44.96
Scandium is a transition metal used in the aerospace and electronic industries.
Give the atomic mass.
(2 d.p)
44.96
Scandium alloys are used in high-end lightweight bicycle frames and sports equipment.
Give the atomic mass.
(2 d.p)
47.87
Titanium is a strong and lightweight metal widely used in the aerospace and medical industries.
Give the atomic mass.
(2 d.p)
47.87
Titanium(IV) oxide is commonly used as a white pigment in paints and cosmetics.
Give the atomic mass.
(2 d.p)
50.94
Vanadium is often used as an alloying element in the production of high-strength steel.
Give the atomic mass.
(2 d.p)
50.94
Vanadium has two naturally-occuring isotopes, V-50 (minor) and V-51 (major).
Give the atomic mass.
(2 d.p)
52.00
Chromium is commonly used as a coating for automotive parts and in stainless steel production.
Give the atomic mass.
(2 d.p)
52.00
Chromium compounds are used in dyes, pigments, and tanning agents.
Give the atomic mass.
(2 d.p)
54.94
Manganese is an essential element for the proper functioning of certain enzymes.
Give the atomic mass.
(2 d.p)
54.94
Manganese is used in steel production and as a component in some batteries.
Give the atomic mass.
(2 d.p)
55.85
Iron is a commonly used metal due to its strength, versatility, and abundance in the Earth’s crust.
Give the atomic mass.
(2 d.p)
55.85
Iron has four naturally-occurring isotopes, with Fe-56 being the most abundant.
Give the atomic mass.
(2 d.p)
58.93
Cobalt is often used in the production of magnets and rechargeable batteries.
Give the atomic mass.
(2 d.p)
58.93
Cobalt compounds are used in the production of blue pigments and as a catalyst.
Give the atomic mass.
(2 d.p)
58.69
Nickel is a silver-white metal often used in the production of stainless steel.
Give the atomic mass.
(2 d.p)
58.69
Nickel is commonly used in the manufacturing of batteries and currency coins.
Give the atomic mass.
(2 d.p)
63.55
Copper is a widely used metal known for its excellent electrical conductivity.
Give the atomic mass.
63.55
Copper is used in electrical wiring, plumbing, and the production of coins.
Give the atomic mass.
(2 d.p)
65.38
Zinc is a bluish-white metal commonly used as a protective coating for iron and steel.
Give the atomic mass.
(2 d.p)
65.38
Zinc has five naturally-occuring isotopes, with Zn-64 being the most abundant
Give the atomic mass.
(2 d.p)
69.72
Gallium is a soft and silvery metal often used in semiconductors and LEDs.
Give the atomic mass.
(2 d.p)
69.72
Gallium compounds are used in medical imaging and as a heat transfer fluid.
Give the atomic mass.
(2 d.p)
72.63
Germanium is a grayish-white metalloid used in the production of semiconductors, however other materials are on the rise for this use.
Give the atomic mass.
(2 d.p)
72.63
Germanium has five naturally-occurring isotopes, and Ge-72 is the most abundant.
Give the atomic mass.
(2 d.p)
74.92
Arsenic is a toxic metalloid used in the production of semiconductors and pesticides, although this second use has been largely discontinued in places such as the USA.
Give the atomic mass.
(2 d.p)
74.92
Out of Arsenic’s 33 known isotopes, only one is stable and naturally occurring (As-75).
Give the atomic mass.
(2 d.p)
78.97
Selenium is a semi-metal commonly used in the production of photovoltaic cells and glass.
Give the atomic mass.
(2 d.p)
78.97
Selenium has 6 naturally-occurring isotopes (Se-74 , 76, 77, 78, 80, 82) of which 5 are stable.
The most abundant isotope is selenium-80.
Give the atomic mass.
(2 d.p)
79.90
Bromine is a reddish-brown liquid halogen commonly used in flame retardants and water disinfection (for non-drinking purposes such as pool water).
Give the atomic mass.
(2 d.p)
79.90
Bromine has 2 naturally-occurring and stable isotopes that are relatively equal in abundance to each other.
These are Br-79 and Br-81.
Give the atomic mass.
(2 d.p)
83.80
Krypton is a noble gas often used in specialized lighting and laser applications.
Give the atomic mass.
(2 d.p)
83.80
Krypton has 32 known isotopes, of which only 6 are stable (Kr-78 , 80 , 82 , 83 , 84 , 86).
Give the atomic mass.
(2 d.p)
85.47
Rubidium is a soft and silvery-white alkali metal with similar physicochemical properties to potassium.
Give the atomic mass.
(2 d.p)
85.47
Rb-85 and Rb-87 are rubidium’s stable, naturally-occurring isotopes, with Rb-85 being by far the most abundant (72.17%).
Give the atomic mass.
(2 d.p)
87.62
Strontium is an alkaline-earth metal commonly used in the production of pyrotechnic compounds.
Give the atomic mass.
(2 d.p)
87.62
Strontium has 4 naturally-occurring, stable isotopes (Sr-84 , 86 , 87 , 88), however its radioisotope Sr-90 is infamous for being a byproduct of nuclear fallouts and its carcinogenic effects.
Give the atomic mass.
(2 d.p)
88.91
Yttrium is a transition metal often used in high-temperature superconductors (as the YBCO compound) and lasers.
Give the atomic mass.
(2 d.p)
88.91
There are many isotopes of yttrium, however Y-89 is the only naturally-occurring and stable one of all of them, making it monoisotopic.
Give the atomic mass.
(2 d.p)
91.22
Zirconium is a corrosion-resistant metal most often used in nuclear reactors and sometimes dental implants.
Give the atomic mass.
(2 d.p)
91.22
Zirconium has 5 naturally-occurring, stable isotopes (Zr-90 , 91, 92 , 94 , 96), with Zr-90 being the most abundant out of all of them.
Give the atomic mass.
(2 d.p)
92.91
Niobium is a transition metal used in alloys for superconducting magnets and in the aerospace industry.
Give the atomic mass.
(2 d.p)
92.91
Nb-93 is the only stable and naturally-occurring isotope of niobium.
Give the atomic mass.
(2 d.p)
95.95
Molybdenum is a transition metal often used in high-strength alloys and as a catalyst.
Give the atomic mass.
(2 d.p)
95.95
Molybdenum has 7 naturally-occcurring, stable isotopes (Mo-92 , 94 , 95 ,96 , 97 , 98 , 100) but Mo-98 is the most abundant (24.39%).
Give the atomic mass.
[98]
Technetium is a radioactive element used in medical imaging and as a tracer in research.
Give the atomic mass.
[98]
Technetium is a synthetic (artificially-produced) transition metal, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
This is because atomic mass is based on naturally-occurring isotopes and their abundances, and so elements with only unstable radioisotopes have an estimated atomic mass.
Give the atomic mass.
(2 d.p)
101.07
Ruthenium is a hard and corrosion-resistant transition metal used in electrical contacts and catalysts.
Give the atomic mass.
(2 d.p)
101.07
Ruthenium has 7 stable, naturally-occurring isotopes (Ru-96 , 98 , 99 , 100 , 101 , 102 , 104), and Ru-102 is the most abundant.
Give the atomic mass.
(2 d.p)
102.91
Rhodium is a rare and precious metal mainly used in catalytic converters and as a coating on optic fibres and optical mirrors.
Give the atomic mass.
(2 d.p)
102.91
Rh-103 is the only stable, naturally-occurring isotope of rhodium, making it monoisotopic.
Give the atomic mass.
(2 d.p)
106.42
Palladium is a precious metal used in catalytic converters, electronics, and jewelry.
Give the atomic mass.
(2 d.p)
106.42
Palladium has 6 stable, naturally-occurring isotopes (Pd-102 , 104 , 105 , 106 , 108 , 110).
Give the atomic mass.
(2 d.p)
107.87
Silver is a precious metal known for its high electrical conductivity and lustrous appearance.
Give the atomic mass.
(2 d.p)
107.87
Ag-107 and Ag-109 are the stable and naturally-occurring isotopes of silver.
Give the atomic mass.
(2 d.p)
112.41
Cadmium is a toxic metal often used in batteries, pigments, and electroplating, but is regulated due to its teratogenic and carcinogenic properties.
Give the atomic mass.
(2 d.p)
112.41
Cadmium has 8 stable, naturally-occurring isotopes, with Cd-114 and Cd-112 being the most abundant respectively.
Give the atomic mass.
(2 d.p)
114.82
Indium is a soft and silvery metal used in semiconductors and liquid crystal displays (LCDs) in the form of indium tin oxide (ITO).
Give the atomic mass.
(2 d.p)
114.82
In-115 is the most abundant of indium’s two stable, naturally-occurring isotopes, the other being In-113.
Give the atomic mass.
(2 d.p)
118.71
Tin has 10 naturally-occurring, stable isotopes, with Sn-120 being the most abundant (32.58%).
Give the atomic mass.
(2 d.p)
118.71
The second most abundant isotope of tin is Sn-118 (24.22%).
Give the atomic mass.
(2 d.p)
121.76
Antimony is a silvery, brittle semi-metal used often in alloys to increase their strength.
Give the atomic mass.
(2 d.p)
121.76
The most stable, naturally-occurring isotope is antimony-121, but its other isotope Sb-123 is quite abundant as well (42.79%).
Give the atomic mass.
(2 d.p)
127.60
Tellurium is a semi-metal that is usually obtained in a grey powder form that can be alloyed with lead to improve its hardness and resistance to acids.
Give the atomic mass.
(2 d.p)
127.60
Te-130 is tellurium’s most abundant natural isotope, but Te-128 follows closely behind this out of the eight total stable isotopes.
Give the atomic mass.
(2 d.p)
126.90
Iodine is a monoisotopic element as it has one stable isotope, I-127.
It does however have one other naturally-occurring isotope (I-129). However this one, along with the other 32, is radioactive.
Give the atomic mass.
(2 d.p)
126.90
Iodine is a halogen commonly used as a disinfectant and as an additive to salt in places with low iodine content in their soil such as New Zealand.
Give the atomic mass.
(2 d.p)
131.29
Xenon is a colorless, odorless noble gas and very unreactive.
It is used in specialised lighting sources.
Give the atomic mass.
(2 d.p)
131.29
Xenon-129 and Xe-132 are xenon’s most stable and abundant isotopes of the 9 naturally-occurring ones.
Give the atomic mass.
(2 d.p)
132.91
Caesium is a soft, gold-coloured alkali metal that reacts explosively with water.
Give the atomic mass.
(2 d.p)
132.91
Caesium has a single stable, naturally-occurring isotope, Cs-133.
Give the atomic mass.
(2 d.p)
137.33
Barium is a soft, silvery metal that rapidly tarnishes in air and reacts with water.
Give the atomic mass.
(2 d.p)
137.33
The most common naturally-occurring and stable isotope of barium’s 7, is Ba-138.
Give the atomic mass.
(2 d.p)
138.91
Lanthanum is a silvery-white lanthanide metal that tarnishes in air and burns easily once ignited.
Give the atomic mass.
(2 d.p)
138.91
Lanthanum-139 is its most abundant isotope, with La-138 also occurring naturally in very small amounts comparatively.
Give the atomic mass.
(2 d.p)
140.12
Cerium is a grey lanthanide metal that is easily tarnished, reactive with water, and burns easily when heated.
Give the atomic mass.
(2 d.p)
140.12
The most abundant isotope of cerium is Ce-140 of its 4 naturally-occurring, stable ones.
Give the atomic mass.
(2 d.p)
140.91
Praseodymium is a soft, silvery lanthanide metal.
Give the atomic mass.
(2 d.p)
140.91
Pr-141 is praseodymium’s only naturally-occurring and stable isotope.
Give the atomic mass.
(2 d.p)
144.24
Neodymium is a silvery-white lanthanide metal that rapidly tarnishes in air.
Give the atomic mass.
(2 d.p)
144.24
The most abundant of neodymium’s 7 naturally-occurring, stable isotopes is Nd-142.
Give the atomic mass.
[145]
Promethium is a radioactive, synthetic lanthanide metal.
Give the atomic mass.
[145]
Promethium is a synthetic (artificially-produced) lanthanide metal, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
This is because atomic mass is based on naturally-occurring isotopes and their abundances, and so elements with only unstable radioisotopes have an estimated atomic mass.
Give the atomic mass.
(2 d.p)
150.36
Samarium is a silvery-white lanthanide metal.
Give the atomic mass.
(2 d.p)
150.36
The most abundant of samarium’s 7 naturally-occurring, stable isotopes is Sm-152.
Give the atomic mass.
(2 d.p)
151.96
Europium is a silvery, soft lanthanide metal that easily tarnishes and reacts with water.
Give the atomic mass.
(2 d.p)
151.96
The most abundant of europium’s 2 naturally-occurring, stable isotopes is Eu-153, but is followed closely by Eu-151.
Give the atomic mass.
(2 d.p)
157.25
Gadolinium is a soft, silvery lanthanide metal that reacts with water and oxygen.
Give the atomic mass.
(2 d.p)
157.25
The most abundant of gadolinium’s 7 naturally-occurring, stable isotopes is Gd-158.
Give the atomic mass.
(2 d.p)
158.93
Terbium is a soft, silvery lanthanide metal.
Give the atomic mass.
(2 d.p)
158.93
Terbium’s only naturally-occurring, stable isotope is Tb-159, making it monoisotopic.
Give the atomic mass.
(2 d.p)
162.50
Dysprosium is a bright, silvery lanthanide metal.
Give the atomic mass.
(2 d.p)
162.50
The most abundant of dysprosium’s 7 naturally-occurring, stable isotopes is Dy-164.
Give the atomic mass.
(2 d.p)
164.93
Holmium is a bright, silvery lanthanide metal.
Give the atomic mass.
(2 d.p)
164.93
Holmium’s only naturally-occurring, stable isotope is Ho-165, making it monoisotopic.
Give the atomic mass.
(2 d.p)
167.26
Erbium is a soft, silvery lanthanide metal.
Give the atomic mass.
(2 d.p)
167.26
The most abundant of erbium’s 6 naturally-occurring, stable isotopes is Er-166.
Give the atomic mass.
(2 d.p)
168.93
Thulium is a bright, silvery lanthanide metal.
Give the atomic mass.
(2 d.p)
168.93
Thulium’s only naturally-occurring, stable isotope is Tm-169, making it monoisotopic.
Give the atomic mass.
(2 d.p)
173.05
Ytterbium is a soft, silvery lanthanide metal that slowly oxidises in air, forming a protective outer-layer.
Give the atomic mass.
(2 d.p)
173.05
The most abundant of ytterbium’s 7 naturally-occurring, stable isotopes is Yb-174.
Give the atomic mass.
(2 d.p)
174.97
Lutetium is a silvery-white, dense, hard lanthanide metal.
Give the atomic mass.
(2 d.p)
174.97
The most abundant of lutetium’s 2 naturally-occurring, stable isotopes is by far Lu-175 (97.40%).
Give the atomic mass.
(2 d.p)
178.49
Hafnium is a lustrous, silvery transition metal that is ductile and resistant to corrosion.
Give the atomic mass.
(2 d.p)
178.49
The most abundant of hafnium’s 6 naturally-occurring, stable isotopes is Hf-180.
Give the atomic mass.
(2 d.p)
180.95
Tantalum is a lustrous, silvery transition metal that is resistant to corrosion.
Give the atomic mass.
(2 d.p)
180.95
The most abundant of tantalum’s 2 naturally-occurring, stable isotopes is undeniably Ta-181 (99.988%).
Give the atomic mass.
(2 d.p)
183.84
Tungsten is a lustrous, silvery-white transition metal.
Give the atomic mass.
(2 d.p)
183.84
The most abundant of tungsten’s 5 naturally-occurring, stable isotopes is W-184.
Give the atomic mass.
(2 d.p)
186.21
Rhenium is a transition metal with the second highest melting point of all the metallic elements.
Give the atomic mass.
(2 d.p)
186.21
The most abundant of rhenium’s 2 naturally-occurring, stable isotopes is Re-187.
Give the atomic mass.
(2 d.p)
190.23
Osmium is a lustrous, silvery metal that is resistant to corrosion and is the densest amongst all elements.
Give the atomic mass.
(2 d.p)
190.23
The most abundant of osmium’s 7 naturally-occurring, stable isotopes is Os-192.
Give the atomic mass.
(2 d.p)
192.22
Iridium is a high-density, hard, silvery transition metal, that has a high melting point and almost is as unreactive as gold.
Give the atomic mass.
(2 d.p)
192.22
The most abundant of iridium’s 2 naturally-occurring, stable isotopes is Ir-193.
Give the atomic mass.
(2 d.p)
195.08
Platinum is a shiny, silvery-white transition metal that is as resistant to corrosion as gold.
Give the atomic mass.
(2 d.p)
195.08
The most abundant of platinum’s 6 naturally-occurring, stable isotopes is Pt-195, followed closely by Pt-194.
Give the atomic mass.
(2 d.p)
196.97
Gold is a precious transition metal renowned for its beauty and resistance to corrosion.
Give the atomic mass.
(2 d.p)
196.97
Au-197 is gold’s one stable isotope, but it also has many more known radioisotopes.
Give the atomic mass.
(2 d.p)
200.59
Mercury is a silvery, heavy transition metal that exists as a liquid at room temperature.
Give the atomic mass.
(2 d.p)
200.59
Mercury has 7 naturally-occurring, stable isotopes (Hg-196 , 198 , 199 , 200 , 201 , 202 , 204).
Hg-202 is the most abundant.
Give the atomic mass.
(2 d.p)
204.38
Thallium is a soft, silvery-white post-transition metal that easily tarnishes.
Give the atomic mass.
(2 d.p)
204.38
The most abundant of thallium’s 2 naturally-occurring, stable isotopes is Tl-205 by far (70.48%).
Give the atomic mass.
(2 d.p)
207.20
Lead is a soft, dull, silvery-grey, and toxic post-transition metal.
Give the atomic mass.
(2 d.p)
207.20
Lead has 4 naturally-occurring, stable isotopes (Pb-204 , 206 , 207 , 208) and many other radioisotopes.
Pb-208 is by far the most abundant.
Give the atomic mass.
(2 d.p)
208.98
Bismuth is a high-density, silvery, pink-tinged post-transition metal.
Give the atomic mass.
(2 d.p)
208.98
Bismuth’s only naturally-occurring, stable isotope is Bi-209, making it monoisotopic.
Give the atomic mass.
[209]
Polonium is a silvery-grey, radioactive metalloid.
Give the atomic mass.
[209]
Polonium is a mostly synthetic (artificially-produced) metalloid, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
It does however occur naturally in minute quantities in uranium ores, it is just uneconomical to extract this.
Give the atomic mass.
[210]
Astatine is a dangerously radioactive, synthetic element and the heaviest member of the halogen group.
Give the atomic mass.
[210]
Astatine is a synthetic (artificially-produced) halogen, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
This is because atomic mass is based on naturally-occurring isotopes and their abundances, and so elements with only unstable radioisotopes have an estimated atomic mass.
Give the atomic mass.
[222]
Radon is a colorless, odorless noble gas that is chemically inert but also radioactive.
Give the atomic mass.
[222]
Radon is a natural noble gas, but is formed from the radioactive decay of radium-226, and so has no stable isotopes. This is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Atomic mass is based on naturally-occurring isotopes and their abundances, and so elements with only unstable radioisotopes have an estimated atomic mass.
Give the atomic mass.
[223]
Francium is intensely radioactive and the heaviest of the alkali metals.
Give the atomic mass.
[223]
Francium is a mostly synthetic (artificially-produced) alkali metal, but does however occur briefly in small quantities as a product of radioactive decay.
Atomic mass is based on naturally-occurring isotopes and their abundances, and so elements with only unstable radioisotopes have an estimated atomic mass and are depicted in square brackets.
Give the atomic mass.
[226]
Radium is a soft, lustrous, silvery radioactive alkaline-earth metal.
Give the atomic mass.
[226]
Radium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[227]
Actinium is a soft, silvery-white, and radioactive actinide metal that has a blue glow surrounding it in the dark.
Give the atomic mass.
[227]
Actinium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
(2 d.p)
232.04
Thorium is a naturally-occurring, silvery, and weakly radioactive actinide metal.
Give the atomic mass.
(2 d.p)
232.04
Thorium’s only naturally-occurring, and relatively stable isotope is Th-232, making it monoisotopic.
Give the atomic mass.
(2 d.p)
231.04
Protactinium is a rare, silvery and highly radioactive actinide metal.
Give the atomic mass.
(2 d.p)
231.04
Protactinium has some naturally-occurring, but no stable isotopes, and the most abundant is Pa-231.
These isotopes however allow for a standard atomic mass to be derived, hence its value is not presented in brackets.
Give the atomic mass.
(2 d.p)
238.03
Uranium is a dense, silvery actinide metal and is the heaviest naturally occurring element.
Give the atomic mass.
(2 d.p)
238.03
Uranium has some naturally-occurring, but no stable isotopes, and the most abundant is by far U-238.
These isotopes however allow for a standard atomic mass to be derived, hence its value is not presented in brackets.
Give the atomic mass.
[237]
Neptunium is a radioactive, silvery actinide metal.
Give the atomic mass.
[237]
Neptunium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[244]
Plutonium is a radioactive, silvery-white, and highly dangerous actinide metal.
Give the atomic mass.
[244]
Plutonium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[243]
Americium is lustrous, silvery, and a radioactive actinide metal.
Give the atomic mass.
[243]
Americium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[247]
Curium is a hard, dense, and silvery-white radioactive actinide metal that tarnishes rapidly in air.
Give the atomic mass.
[247]
Curium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[247]
Berkelium is a silvery, radioactive transuranium actinide metal.
Give the atomic mass.
[247]
Berkelium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[251]
Californium is a radioactive actinide metal.
Give the atomic mass.
[251]
Californium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[252]
Einsteinium is a radioactive transuranium actinide metal.
Give the atomic mass.
[252]
Einsteinium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[257]
Fermium is a synthetic, radioactive actinide metal.
Give the atomic mass.
[257]
Fermium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[258]
Mendelevium is a synthetic, radioactive actinide metal.
Give the atomic mass.
[258]
Mendelevium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[259]
Nobelium is a synthetic, radioactive actinide metal.
Give the atomic mass.
[259]
Nobelium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[262]
Lawrencium is a radioactive, synthetic actinide metal.
Give the atomic mass.
[262]
Lawrencium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[267]
Rutherfordium is a synthetic and highly radioactive transuranic element.
Give the atomic mass.
[267]
Rutherfordium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[268]
Dubnium is a radioactive, synthetic transuranium metal.
Give the atomic mass.
[268]
Dubnium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[269]
Seaborgium is a synthetic, radioactive transuranic metal.
Give the atomic mass.
[269]
Seaborgium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[270]
Bohrium is a synthetic and highly radioactive transuranic element.
Give the atomic mass.
[270]
Bohrium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[269]
Hassium is a synthetic transuranic element and its most stable isotope has a half-life of approximately 9.7 seconds.
Give the atomic mass.
[269]
Hassium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[278]
Meitnerium is a synthetic and highly radioactive transuranic element.
Give the atomic mass.
[278]
Meitnerium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[281]
Darmstadtium is a highly radioactive, synthetic transuranium metal.
Give the atomic mass.
[281]
Darmstadtium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[282]
Roentgenium is a synthetic and highly unstable transuranium element.
Give the atomic mass.
[282]
Roentgenium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[285]
Copernicium is a synthetic and highly radioactive transuranic element.
Give the atomic mass.
[285]
Copernicium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[286]
Nihonium is a synthetic and highly radioactive transuranium metal.
Give the atomic mass.
[286]
Nihonium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[289]
Flerovium is a synthetic and highly radioactive transuranium metal.
Give the atomic mass.
[289]
Flerovium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[290]
Moscovium is a synthetic and highly radioactive transuranium metal.
Give the atomic mass.
[290]
Moscovium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[293]
Livermorium is a synthetic and highly radioactive transuranium metal.
Give the atomic mass.
[293]
Livermorium has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[294]
Tennessine is a synthetic and highly radioactive transuranium element included in the halogen group.
Give the atomic mass.
[294]
Tennessine has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
[294]
Oganesson is a synthetic and highly radioactive transuranium metal.
Give the atomic mass.
[294]
Oganesson has no stable isotopes, which is indicated by its atomic mass being commonly represented as a whole-number contained within square brackets.
Give the atomic mass.
(2 d.p)
20.18
Neon is an unreactive element and classified as a noble gas.
Give the atomic mass.
(2 d.p)
20.18
Neon has three key isotopes, Ne-20, Ne-21, and Ne-22, with Ne-20 by far being the most abundant (around 90%).
