????????

Polonium, ₈₄Po
?????? ???
???, ??????	polonium, Po
Appearance	silvery
???????	/ p [invalid input: '?'] ? l o? n i ? m / po- LOH -nee-?m
Polonium in the periodic table
	bismuth ← polonium → astatine
?????? ???????? ( Z )	84
?????? , ????	group 16 (chalcogens) , p-block
????????	period 6
????? ??????	post-transition metal , post-transition metal status is disputed (see article text)
???? ???????? ??? ( A r )	(209)
???????????? ???????	[ Xe ] 6s 2 4f 14 5d 10 6p 4
per shell	2, 8, 18, 32, 18, 6
????? ???
??????	solid
???????	527 K (254 °C, 489 °F)
??????????	1235 K (962 °C, 1764 °F)
Density near r.t.	(alpha) 9.196 g/cm 3 ; (beta) 9.398 g/cm 3
Heat of fusion	ca. 13 kJ/mol
Heat of	102.91 kJ/mol
Molar heat capacity	26.4 J/(mol·K)
Atomic properties
Oxidation states	6, 4 , 2, ?2 ; ( amphoteric oxide)
Electronegativity	Pauling scale: 2.0
Atomic radius	empirical: 168 pm
Covalent radius	140±4 pm
Van der Waals radius	197 pm
Miscellanea
Crystal structure	cubic
Thermal expansion	23.5 μm/(m·K) (at 25 °C)
Thermal conductivity	? 20 W/(m·K)
Electrical resistivity	(α) 0.40 μ Ω·m (at 0 °C)
Magnetic ordering	nonmagnetic
CAS Number	7440-08-6
??????
????????	Pierre Curie and Marie Curie (1898)
First isolation	Willy Marckwald (1902)
Most stable isotopes of polonium
	view ; talk ; edit ; \| references