cesium

cesium (chemical element)

Periodic table location

Image

atomic symbol | Cs atomic number | 55 short electronic configuration | [Xe]6s^1 Aufbau diagram | 6s block | s group | 1 period | 6 atomic mass | 132.90545196 u (unified atomic mass units)

phase at STP | solid melting point | 28.44 °C (rank: 89th) boiling point | 671 °C (rank: 77th) critical temperature | 1938 K (rank: 5th) critical pressure | 9.4 MPa (rank: 10th) molar heat of fusion | 2.09 kJ/mol (rank: 82nd) molar heat of vaporization | 65 kJ/mol (rank: 73rd) specific heat at STP | 242 J/(kg K) (rank: 44th) (properties at standard conditions)

density | 1.879 g/cm^3 (rank: 77th) liquid density | 1.843 g/cm^3 molar volume | 70.73 cm^3/mol Mohs hardness | 0.2 (between talc and gypsum) Brinell hardness | 0.14 MPa (rank: 60th) bulk modulus | 1.6 GPa (rank: 68th) Young's modulus | 1.7 GPa (rank: 63rd) thermal conductivity | 36 W/(m K) (rank: 40th) (properties at standard conditions)

electrical type | conductor resistivity | 2×10^-7 Ω m (ohm meters) electrical conductivity | 5×10^6 S/m (siemens per meter) magnetic type | paramagnetic volume magnetic susceptibility | 5.26×10^-6 mass magnetic susceptibility | 2.8×10^-9 m^3/kg (cubic meters per kilogram) molar magnetic susceptibility | 3.72×10^-10 m^3/mol (cubic meters per mole) work function | 1.95 eV (Polycrystalline) threshold frequency | 4.715×10^14 Hz (hertz) color | (yellow)

valence | 1 electronegativity | 0.79 electron affinity | 45.5 kJ/mol (kilojoules per mole) first ionization energy | 375.7 kJ/mol (kilojoules per mole) ionization energies | 375.7 kJ/mol | 2234.3 kJ/mol | 3400 kJ/mol

Reactivity

term symbol | ^2S_(1/2) atomic radius | 260 pm covalent radius | 244 pm (electronic ground state properties)

(neutral cesium atomic spectrum)

universe abundance | 8×10^-8 mass% (rank: 65th) solar abundance | 8×10^-7 mass% (rank: 41st) meteorite abundance | 1.4×10^-5 mass% (rank: 62nd) crust abundance | 1.9×10^-4 mass% (rank: 50th) ocean abundance | 5×10^-8 mass% (rank: 34th) human abundance | 2×10^-6 mass% (rank: 37th) universe molar abundance | 1×10^-9 mol% (rank: 59th) solar molar abundance | 7×10^-9 mol% (rank: 39th) meteorite molar abundance | 2×10^-6 mol% (rank: 56th) ocean molar abundance | 2.3×10^-9 mol% (rank: 47th) crust molar abundance | 2.9×10^-5 mol% (rank: 52nd) human molar abundance | 1×10^-7 mol% (rank: 39th)

half-life | (stable) stable isotopes | Cs-133 (100%) nuclear spin | Cs-113: 3/2^+ | Cs-114: 1^+ | Cs-115: 9/2^+ | Cs-116: 1^+ | Cs-117: 9/2^+ | Cs-118: 2^? | Cs-119: 9/2^+ | Cs-120: 2^+ | Cs-121: 3/2^+ | Cs-122: 1^+ | Cs-123: 1/2^+ | Cs-124: 1^+ | Cs-125: 1/2^+ | Cs-126: 1^+ | Cs-127: 1/2^+ | Cs-128: 1^+ | Cs-129: 1/2^+ | Cs-130: 1^+ | Cs-131: 5/2^+ | Cs-132: 2^+ | Cs-133: 7/2^+ | Cs-134: 4^+ | Cs-135: 7/2^+ | Cs-136: 5^+ | Cs-137: 7/2^+ | Cs-138: 3^- | Cs-139: 7/2^+ | Cs-140: 1^- | Cs-141: 7/2^+ | Cs-142: 0^- | Cs-143: 3/2^+ | Cs-144: 1^- | Cs-145: 3/2^+ | Cs-146: 1^- | Cs-147: 3/2^+ | Cs-149: 3/2^+ | Cs-151: 3/2^+ unstable isotopes | Cs-135 (2.3 Myr) | Cs-137 (30.08 yr) | Cs-134 (2.0652 yr) | Cs-136 (13.04 days) | Cs-131 (9.689 days) | Cs-132 (6.479 days) | Cs-129 (32.06 h) | Cs-127 (6.25 h) | Cs-125 (46.7 min) | Cs-138 (33.42 min) | Cs-130 (29.22 min) | Cs-139 (9.27 min) | Cs-123 (5.87 min) | Cs-128 (220 s) | Cs-121 (155 s) | Cs-126 (98.4 s) | Cs-140 (63.7 s) | Cs-120 (61.2 s) | Cs-119 (43 s) | Cs-124 (30.9 s) | Cs-141 (24.84 s) | Cs-122 (21.18 s) | Cs-118 (14 s) | Cs-117 (8.4 s) | Cs-143 (1.791 s) | Cs-142 (1.684 s) | Cs-115 (1.4 s) | Cs-144 (0.994 s) | Cs-116 (700 ms) | Cs-145 (587 ms) | Cs-114 (570 ms) | Cs-146 (321 ms) | Cs-147 (235 ms) | Cs-148 (146 ms) | Cs-151 (50 ms) | Cs-150 (50 ms) | Cs-149 (50 ms) | Cs-112 (500 µs) | Cs-113 (16.7 µs) neutron cross-section | 29 b neutron mass absorption | 0.0077 m^2/kg

CAS number | 7440-46-2 PubChem CID number | 5354618