| ngoi-kôn |
|---|
silvery white metallic
 |
| Kî-pún sin-sit |
|---|
| Miàng, fù-ho |
radium, Ra |
|---|
| ngoi-hìn |
silvery white metallic |
|---|
| Radium chhai chû-khì-péu ke vi-chi |
|---|
|
|
| ngièn-chṳ́ sì-sú |
88 |
|---|
| ngièn-chṳ́-liòng |
(226) |
|---|
| ngièn-su lui-phe̍t |
kán-thú kîm-su̍k |
|---|
| Chhu̍k, fûn-khî |
2 chhu̍k, s-block |
|---|
| chû-khì |
period 7 |
|---|
| thien-chṳ́ phài-lie̍t |
[Rn] 7s2 |
|---|
| per shell |
2, 8, 18, 32, 18, 8, 2 |
|---|
| vu̍t-lî sin-chṳt |
|---|
| Siông |
ku-thí |
|---|
| yùng-tiám |
973 K (700 °C, 1292 °F) (disputed) |
|---|
| pui-tiám |
2010 K (1737 °C, 3159 °F) |
|---|
| Me̍t-thu near Sit-vûn |
5.5 g·cm−3 |
|---|
| Yùng-fa-ngie̍t |
8.5 kJ·mol−1 |
|---|
| Chîn-fat-ngie̍t |
113 kJ·mol−1 |
|---|
chîn-hi-ap
| P (Pa)
|
1
|
10
|
100
|
1 k
|
10 k
|
100 k
| | chhai T (K)
|
819
|
906
|
1037
|
1209
|
1446
|
1799
|
|
| Ngièn-chṳ́ sin-chṳt |
|---|
| Yông-fa-su |
2 (expected to have a strongly basic oxide) |
|---|
| Thien-fu-sin |
Pauling scale: 0.9 |
|---|
| Thien-lì-nèn |
1st: 509.3 kJ·mol−1
2nd: 979.0 kJ·mol−1 |
|---|
| Khiung-ka pan-kang |
221±2 pm |
|---|
| Van der Waals pan-kang |
283 pm |
|---|
| Miscellanea |
|---|
| Chîn-thí keu-chho |
body-centered cubic (bcc) |
|---|
| Ngie̍t-chhòn-thô-li̍t |
18.6 W·m−1·K−1 |
|---|
| Thien-chú-li̍t |
1 µΩ·m (at 20 °C) |
|---|
| Chhṳ̀-sin |
nonmagnetic |
|---|
| CAS Registry Number |
7440-14-4 |
|---|
| Le̍k-sú |
|---|
| Fat-hien |
Pierre Curie and Marie Curie (1898) |
|---|
| First isolation |
Marie Curie (1910) |
|---|
| Chui vún-thin ke thùng-vi-su |
|---|
|
Chú vùn-chông: radium ke thùng-vi-su |
| iso
|
NA
|
half-life
|
DM
|
DE (MeV)
|
DP
|
|---|
| 223Ra
|
trace
|
11.43 d
|
α
|
5.99
|
219Rn
| | 224Ra
|
trace
|
3.6319 d
|
α
|
5.789
|
220Rn
| | 225Ra
|
trace
|
14.9 d
|
β−
|
0.356
|
225Ac
| | 226Ra
|
trace
|
1600 y
|
α
|
4.871
|
222Rn
| | 228Ra
|
trace
|
5.75 y
|
β− |
0.046
|
228Ac
|
|
