| Atomic Number | 87 | 
|---|---|
| Atomic Weight | 223 | 
| mass number | 197 | 
| Group | 1 | 
|---|---|
| Period | 7 | 
| Block | s | 
| proton | 87 p+ | 
|---|---|
| neutron | 110 n0 | 
| electron | 87 e- | 
| Atomic Radius | |
|---|---|
| molar volume | |
| Covalent Radius | |
| Metallic Radius | |
| ionic radius | |
| Crystal Radius | |
| Van der Waals radius | |
| density | 
| energy | |
|---|---|
| proton affinity | |
| electron affinity | |
| ionization energy | |
| enthalpy of vaporization | |
| enthalpy of fusion | |
| standard enthalpy of formation | |
| electron | |
| electron shell | 2, 8, 18, 32, 18, 8, 1 | 
| valence electron | 1 ⓘ | 
| electron configuration | [Rn] 7s1ⓘ 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s1 | 
| oxidation number | 1 | 
| electronegativity | 0.7 | 
| Electrophilicity Index | |
| fundamental state of matter | |
| phase of matter{ERROR} | |
| gaseous state of matter | |
| Boiling Point | |
| Melting Point | |
| critical pressure | |
| critical temperature | |
| triple point | |
| appearance | |
| color | Black | 
| appearance | |
| refractive index | |
| thermodynamic material property | |
| Thermal Conductivity | |
| thermal expansion | |
| molar heat capacity | |
| Specific Heat Capacity | |
| heat capacity ratio | |
| electrical properties | |
| type | |
| electrical conductivity | |
| electrical resistivity | |
| superconductivity | |
| magnetism | |
| type | |
| magnetic susceptibility (Mass) | |
| magnetic susceptibility (Molar) | |
| magnetic susceptibility (Volume) | |
| magnetic ordering | |
| Curie temperature | |
| Néel temperature | |
| structure | |
| Crystal Structure | {ERROR} | 
| lattice constant | |
| Lattice Angles | |
| mechanical property | |
| hardness | |
| bulk modulus | |
| shear modulus | |
| Young's modulus | |
| Poisson's ratio | |
| speed of sound | |
| classification | |
| Category | Actinides, Alkali metals | 
| CAS Group | IA | 
| IUPAC Group | IA | 
| Glawe Number | 7 | 
| Mendeleev Number | 6 | 
| Pettifor Number | 7 | 
| Geochemical Class | U/Th decay series | 
| Goldschmidt classification | synthetic | 
| Gas Basicity | |
|---|---|
| polarizability | |
| C6 Dispersion Coefficient | |
| allotrope | |
| Neutron cross section | |
| Neutron Mass Absorption | |
| quantum number | 2S1/2 | 
| space group | () | 
| Stable Isotopes | 0 | 
|---|---|
| Unstable Isotopes | 37 | 
| Natural Isotopes | 0 | 
| mass number | 197 | 
|---|---|
| neutron number | 110 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 2.3 ± 1.9 ms | 
| spin | 7/2 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 2013 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| mass number | 198 | 
|---|---|
| neutron number | 111 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 15 ± 3 ms | 
| spin | 3 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 2013 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| mass number | 199 | 
|---|---|
| neutron number | 112 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 6.6 ± 2.2 ms | 
| spin | 1/2 | 
| nuclear quadrupole moment | 0  | 
| time of discovery or invention | 1999 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| β+ (β+ decay; β+ = ϵ + e+) | 
| mass number | 200 | 
|---|---|
| neutron number | 113 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 47.5 ± 2.8 ms | 
| spin | 3 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 1995 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| β+ (β+ decay; β+ = ϵ + e+) | |
| β+ SF (β+-delayed fission) | 
| mass number | 201 | 
|---|---|
| neutron number | 114 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 62.8 ± 1.9 ms | 
| spin | 9/2 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 1980 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| β+ (β+ decay; β+ = ϵ + e+) | 
| mass number | 202 | 
|---|---|
| neutron number | 115 | 
| Relative Atomic Mass | |
| g-factor | 1.3 ± 0.016666666666667  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 372 ± 12 ms | 
| spin | 3 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 1980 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| β+ (β+ decay; β+ = ϵ + e+) | 
| mass number | 203 | 
|---|---|
| neutron number | 116 | 
| Relative Atomic Mass | |
| g-factor | 0.83111111111111 ± 0.0088888888888889  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 550 ± 10 ms | 
| spin | 9/2 | 
| nuclear quadrupole moment | -0.47 ± 0.02  | 
| time of discovery or invention | 1967 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| β+ (β+ decay; β+ = ϵ + e+) | 
| mass number | 204 | 
|---|---|
| neutron number | 117 | 
| Relative Atomic Mass | |
| g-factor | 1.33 ± 0.01  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 1.75 ± 0.26 s | 
| spin | 3 | 
| nuclear quadrupole moment | -0.141 ± 0.009  | 
| time of discovery or invention | 1964 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 96% | 
| β+ (β+ decay; β+ = ϵ + e+) | 
| mass number | 205 | 
|---|---|
| neutron number | 118 | 
| Relative Atomic Mass | |
| g-factor | 0.84444444444444 ± 0.0066666666666667  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 3.9 ± 0.07 s | 
| spin | 9/2 | 
| nuclear quadrupole moment | -0.305 ± 0.018  | 
| time of discovery or invention | 1964 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 98.5% | 
| β+ (β+ decay; β+ = ϵ + e+) | 1.5% | 
| mass number | 206 | 
|---|---|
| neutron number | 119 | 
| Relative Atomic Mass | |
| g-factor | 1.3233333333333 ± 0.016666666666667  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | |
| spin | 3 | 
| nuclear quadrupole moment | -0.354 ± 0.009  | 
| time of discovery or invention | 1964 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 88.4% | 
| β+ (β+ decay; β+ = ϵ + e+) | 11.6% | 
| mass number | 207 | 
|---|---|
| neutron number | 120 | 
| Relative Atomic Mass | |
| g-factor | 0.86 ± 0.0088888888888889  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 14.8 ± 0.1 s | 
| spin | 9/2 | 
| nuclear quadrupole moment | -0.24 ± 0.02  | 
| time of discovery or invention | 1964 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 95% | 
| β+ (β+ decay; β+ = ϵ + e+) | 
| mass number | 208 | 
|---|---|
| neutron number | 121 | 
| Relative Atomic Mass | |
| g-factor | 0.67285714285714 ± 0.0057142857142857  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 59.1 ± 0.3 s | 
| spin | 7 | 
| nuclear quadrupole moment | 0.052 ± 0.011  | 
| time of discovery or invention | 1964 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 89% | 
| β+ (β+ decay; β+ = ϵ + e+) | 11% | 
| mass number | 209 | 
|---|---|
| neutron number | 122 | 
| Relative Atomic Mass | |
| g-factor | 0.87333333333333 ± 0.011111111111111  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 50.5 ± 0.7 s | 
| spin | 9/2 | 
| nuclear quadrupole moment | -0.26 ± 0.02  | 
| time of discovery or invention | 1964 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 89% | 
| β+ (β+ decay; β+ = ϵ + e+) | 11% | 
| mass number | 210 | 
|---|---|
| neutron number | 123 | 
| Relative Atomic Mass | |
| g-factor | 0.73 ± 0.0083333333333333  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 3.18 ± 0.06 m | 
| spin | 6 | 
| nuclear quadrupole moment | 0.21 ± 0.02  | 
| time of discovery or invention | 1964 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 71% | 
| β+ (β+ decay; β+ = ϵ + e+) | 
| mass number | 211 | 
|---|---|
| neutron number | 124 | 
| Relative Atomic Mass | |
| g-factor | 0.88222222222222 ± 0.011111111111111  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 3.1 ± 0.02 m | 
| spin | 9/2 | 
| nuclear quadrupole moment | -0.21 ± 0.02  | 
| time of discovery or invention | 1964 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 87% | 
| β+ (β+ decay; β+ = ϵ + e+) | 13% | 
| mass number | 212 | 
|---|---|
| neutron number | 125 | 
| Relative Atomic Mass | |
| g-factor | 0.918 ± 0.01  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 20 ± 0.6 m | 
| spin | 5 | 
| nuclear quadrupole moment | -0.1 ± 0.002  | 
| time of discovery or invention | 1950 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| β+ (β+ decay; β+ = ϵ + e+) | 57% | 
| α (α emission) | 43% | 
| mass number | 213 | 
|---|---|
| neutron number | 126 | 
| Relative Atomic Mass | |
| g-factor | 0.88666666666667 ± 0.0022222222222222  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 34.14 ± 0.06 s | 
| spin | 9/2 | 
| nuclear quadrupole moment | -0.138 ± 0.003  | 
| time of discovery or invention | 1964 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 99.44% | 
| β+ (β+ decay; β+ = ϵ + e+) | 0.56% | 
| mass number | 214 | 
|---|---|
| neutron number | 127 | 
| Relative Atomic Mass | |
| g-factor | 0.241 ± 0.016  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 5.51 ± 0.13 ms | 
| spin | 1 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 1967 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| mass number | 215 | 
|---|---|
| neutron number | 128 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 90 ± 4 ns | 
| spin | 9/2 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 1970 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| mass number | 216 | 
|---|---|
| neutron number | 129 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 700 ± 20 ns | 
| spin | 1 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 1970 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| β+ (β+ decay; β+ = ϵ + e+) | 
| mass number | 217 | 
|---|---|
| neutron number | 130 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 22 ± 5 us | 
| spin | 9/2 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 1968 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| mass number | 218 | 
|---|---|
| neutron number | 131 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 1.4 ± 0.5 ms | 
| spin | 1 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 1949 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| mass number | 219 | 
|---|---|
| neutron number | 132 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 22.5 ± 1.7 ms | 
| spin | 9/2 | 
| nuclear quadrupole moment | -1.19 ± 0.02  | 
| time of discovery or invention | 1948 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| mass number | 220 | 
|---|---|
| neutron number | 133 | 
| Relative Atomic Mass | |
| g-factor | -0.66 ± 0.01  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 27.4 ± 0.3 s | 
| spin | 1 | 
| nuclear quadrupole moment | 0.487 ± 0.008  | 
| time of discovery or invention | 1948 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| β− (β− decay) | 0.35% | 
| mass number | 221 | 
|---|---|
| neutron number | 134 | 
| Relative Atomic Mass | |
| g-factor | 0.628 ± 0.008  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 4.801 ± 0.005 m | 
| spin | 5/2 | 
| nuclear quadrupole moment | -1.02 ± 0.03  | 
| time of discovery or invention | 1947 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| α (α emission) | 100% | 
| β− (β− decay) | 0.0048% | 
| 14C | 8.8% | 
| mass number | 222 | 
|---|---|
| neutron number | 135 | 
| Relative Atomic Mass | |
| g-factor | 0.315 ± 0.005  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 14.2 ± 0.3 m | 
| spin | 2 | 
| nuclear quadrupole moment | 0.51 ± 0.04  | 
| time of discovery or invention | 1975 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| mass number | 223 | 
|---|---|
| neutron number | 136 | 
| Relative Atomic Mass | |
| g-factor | 0.77333333333333 ± 0.0066666666666667  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 22 ± 0.07 m | 
| spin | 3/2 | 
| nuclear quadrupole moment | 1.18 ± 0.02  | 
| time of discovery or invention | 1939 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| α (α emission) | 0.006% | 
| mass number | 224 | 
|---|---|
| neutron number | 137 | 
| Relative Atomic Mass | |
| g-factor | 0.4 ± 0.01  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 3.33 ± 0.1 m | 
| spin | 1 | 
| nuclear quadrupole moment | 0.523 ± 0.009  | 
| time of discovery or invention | 1969 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| mass number | 225 | 
|---|---|
| neutron number | 138 | 
| Relative Atomic Mass | |
| g-factor | 0.70666666666667 ± 0.0066666666666667  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 3.95 ± 0.14 m | 
| spin | 3/2 | 
| nuclear quadrupole moment | 1.33 ± 0.02  | 
| time of discovery or invention | 1969 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| mass number | 226 | 
|---|---|
| neutron number | 139 | 
| Relative Atomic Mass | |
| g-factor | 0.0712 ± 0.0014  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 48.5 ± 0.7 s | 
| spin | 1 | 
| nuclear quadrupole moment | -1.37 ± 0.03  | 
| time of discovery or invention | 1969 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| mass number | 227 | 
|---|---|
| neutron number | 140 | 
| Relative Atomic Mass | |
| g-factor | 2.98 ± 0.04  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 2.47 ± 0.03 m | 
| spin | 1/2 | 
| nuclear quadrupole moment | 0  | 
| time of discovery or invention | 1972 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| mass number | 228 | 
|---|---|
| neutron number | 141 | 
| Relative Atomic Mass | |
| g-factor | -0.38 ± 0.005  | 
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 38 ± 1 s | 
| spin | 2 | 
| nuclear quadrupole moment | 2.41 ± 0.06  | 
| time of discovery or invention | 1972 | 
| parity | - | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| mass number | 229 | 
|---|---|
| neutron number | 142 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 50.2 ± 0.4 s | 
| spin | 1/2 | 
| nuclear quadrupole moment | 0  | 
| time of discovery or invention | 1975 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| mass number | 230 | 
|---|---|
| neutron number | 143 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 19.1 ± 0.5 s | 
| spin | 2 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 1987 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| mass number | 231 | 
|---|---|
| neutron number | 144 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 17.6 ± 0.6 s | 
| spin | 1/2 | 
| nuclear quadrupole moment | 0  | 
| time of discovery or invention | 1985 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| mass number | 232 | 
|---|---|
| neutron number | 145 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 5.5 ± 0.6 s | 
| spin | 5 | 
| nuclear quadrupole moment | |
| time of discovery or invention | 1990 | 
| parity | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| β− SF (β−-delayed fission) | 
| mass number | 233 | 
|---|---|
| neutron number | 146 | 
| Relative Atomic Mass | |
| g-factor | |
| natural abundance | |
| radioactivity | ☢️ radioactive element | 
| half-life | 900 ± 100 ms | 
| spin | 1/2 | 
| nuclear quadrupole moment | 0  | 
| time of discovery or invention | 2010 | 
| parity | + | 
| decay mode | intensity | 
|---|---|
| β− (β− decay) | 100% | 
| β− n (β−-delayed neutron emission) | 

| discoverer or inventor | Marguerite Derey | 
|---|---|
| location of discovery | France | 
| time of discovery or invention | 1939 | 
| etymology | Named for France, the nation of its discovery. | 
| pronunciation | FRAN-si-em (English) | 
| Abundance | |
|---|---|
| Abundance in Earth's crust | |
| natural abundance (ocean) | |
| natural abundance (Human body) | 0 % | 
| natural abundance (meteoroid) | |
| natural abundance (La) | |
| Abundance in Universe | 0 % |