sodium, cesium

sodium (chemical element) | cesium (chemical element)

Periodic table location

Images

| sodium | cesium atomic symbol | Na | Cs atomic number | 11 | 55 short electronic configuration | [Ne]3s^1 | [Xe]6s^1 Aufbau diagram | 3s | 6s block | s | s group | 1 | 1 period | 3 | 6 atomic mass | 22.98976928 u | 132.90545196 u half-life | (stable) | (stable)

| sodium | cesium phase at STP | solid | solid melting point | 97.72 °C | 28.44 °C boiling point | 883 °C | 671 °C critical temperature | 2573 K | 1938 K critical pressure | 35 MPa | 9.4 MPa molar heat of fusion | 2.6 kJ/mol | 2.09 kJ/mol molar heat of vaporization | 97.7 kJ/mol | 65 kJ/mol specific heat at STP | 1230 J/(kg K) | 242 J/(kg K) (properties at standard conditions)

| sodium | cesium density | 0.968 g/cm^3 | 1.879 g/cm^3 liquid density | 0.927 g/cm^3 | 1.843 g/cm^3 molar volume | 23.7 cm^3/mol | 70.73 cm^3/mol Mohs hardness | 0.5 (between talc and gypsum) | 0.2 (between talc and gypsum) Brinell hardness | 0.69 MPa | 0.14 MPa bulk modulus | 6.3 GPa | 1.6 GPa shear modulus | 3.3 GPa | Young's modulus | 10 GPa | 1.7 GPa ultimate tensile strength | 10 MPa | sound speed | 3200 m/s | thermal expansion | 7.1×10^-5 K^(-1) | thermal conductivity | 140 W/(m K) | 36 W/(m K) (properties at standard conditions)

| sodium | cesium electrical type | conductor | conductor resistivity | 4.7×10^-8 Ω m (ohm meters) | 2×10^-7 Ω m (ohm meters) electrical conductivity | 2.1×10^7 S/m (siemens per meter) | 5×10^6 S/m (siemens per meter) magnetic type | paramagnetic | paramagnetic volume magnetic susceptibility | 8.5×10^-6 | 5.26×10^-6 mass magnetic susceptibility | 8.8×10^-9 m^3/kg (cubic meters per kilogram) | 2.8×10^-9 m^3/kg (cubic meters per kilogram) molar magnetic susceptibility | 2×10^-10 m^3/mol (cubic meters per mole) | 3.72×10^-10 m^3/mol (cubic meters per mole) work function | 2.36 eV (Polycrystalline) | 1.95 eV (Polycrystalline) threshold frequency | 5.706×10^14 Hz (hertz) | 4.715×10^14 Hz (hertz) color | (silver) | (yellow)

| sodium | cesium valence | 1 | 1 electronegativity | 0.93 | 0.79 electron affinity | 52.8 kJ/mol (kilojoules per mole) | 45.5 kJ/mol (kilojoules per mole) first ionization energy | 495.8 kJ/mol (kilojoules per mole) | 375.7 kJ/mol (kilojoules per mole) ionization energies | 495.8 kJ/mol | 4562 kJ/mol | 6910.3 kJ/mol | 9543 kJ/mol | 13354 kJ/mol | 16613 kJ/mol | 20117 kJ/mol | 25496 kJ/mol | 28932 kJ/mol | 141362 kJ/mol | 375.7 kJ/mol | 2234.3 kJ/mol | 3400 kJ/mol

Reactivity

| sodium | cesium term symbol | ^2S_(1/2) | ^2S_(1/2) atomic radius | 180 pm | 260 pm covalent radius | 166 pm | 244 pm van der Waals radius | 227 pm | (electronic ground state properties)

| sodium | cesium universe abundance | 0.002 mass% | 8×10^-8 mass% solar abundance | 0.004 mass% | 8×10^-7 mass% meteorite abundance | 0.55 mass% | 1.4×10^-5 mass% crust abundance | 2.3 mass% | 1.9×10^-4 mass% ocean abundance | 1.1 mass% | 5×10^-8 mass% human abundance | 0.14 mass% | 2×10^-6 mass% universe molar abundance | 1×10^-4 mol% | 1×10^-9 mol% solar molar abundance | 2×10^-4 mol% | 7×10^-9 mol% meteorite molar abundance | 0.48 mol% | 2×10^-6 mol% ocean molar abundance | 0.3 mol% | 2.3×10^-9 mol% crust molar abundance | 2.1 mol% | 2.9×10^-5 mol% human molar abundance | 0.038 mol% | 1×10^-7 mol%

| sodium | cesium half-life | (stable) | (stable) stable isotopes | Na-23 (100%) | Cs-133 (100%) nuclear spin | Na-18: 1^- | Na-19: 5/2^+ | Na-20: 2^+ | Na-21: 3/2^+ | Na-22: 3^+ | Na-23: 3/2^+ | Na-24: 4^+ | Na-25: 5/2^+ | Na-26: 3^+ | Na-27: 5/2^+ | Na-28: 1^+ | Na-29: 3/2^+ | Na-30: 2^+ | Na-31: 3/2^+ | Na-33: 3/2^+ | Na-34: 1^+ | Na-35: 3/2^+ | Na-37: 3/2^+ | 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 | Na-22 (2.6027 yr) | Na-24 (14.997 h) | Na-25 (59.1 s) | Na-21 (22.49 s) | Na-26 (1.077 s) | Na-20 (447.9 ms) | Na-27 (301 ms) | Na-30 (48.4 ms) | Na-29 (44.9 ms) | Na-28 (30.5 ms) | Na-31 (17 ms) | Na-32 (13.2 ms) | Na-33 (8 ms) | Na-34 (5.5 ms) | Na-35 (1.5 ms) | Na-36 (180 ns) | Na-37 (60 ns) | Na-19 (40 ns) | Na-18 (1.3 zs) | 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 | 0.53 b | 29 b neutron mass absorption | 7×10^-4 m^2/kg | 0.0077 m^2/kg

| sodium | cesium CAS number | 7440-23-5 | 7440-46-2 PubChem CID number | 5360545 | 5354618