Rédíọ́mù (pípè /ˈradiəmu/, RAY-dee-əm) jẹ́ ìpilẹ̀ṣẹ̀ kẹ́míkà tó ní àmì-ìdímọ̀ Ra àti nọ́ḿbà átọ̀mù 88.
Quick facts Radium, Pípè ...
Radium, 88Ra| Radium |
|---|
| Pípè | /ˈreɪdiəm/ (RAY-dee-əm) |
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| Ìhànsójú | silvery white metallic |
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| nọ́mbà ìsújọ | [226] |
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| Radium ní orí tábìlì àyè |
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|
|
| Nọ́mbà átọ̀mù (Z) | 88 |
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| Ẹgbẹ́ | group 2 (alkaline earth metals) |
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| Àyè | àyè 7 |
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| Àdìpọ̀ | Àdìpọ̀-s |
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| Ẹ̀ka ẹ́límẹ́ntì | Alkaline earth metal |
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| Ìtò ẹ̀lẹ́ktrọ́nù | [Rn] 7s2 |
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| Iye ẹ̀lẹ́ktrọ́nù lórí ìpele kọ̀ọ̀kan | 2, 8, 18, 32, 18, 8, 2 |
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| Àwọn ohun ìní ara |
|---|
| Ìfarahàn at STP | solid |
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| Ìgbà ìyọ́ | 973 K (700 °C, 1292 °F) |
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| Ígbà ìhó | 2010 K (1737 °C, 3159 °F) |
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| Kíki (near r.t.) | 5.5 g/cm3 |
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| Heat of fusion | 8.5 kJ/mol |
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| Heat of | 113 kJ/mol |
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pressure
| P (Pa) |
1 |
10 |
100 |
1 k |
10 k |
100 k |
| at T (K) |
819 |
906 |
1037 |
1209 |
1446 |
1799 |
|
| Atomic properties |
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| Oxidation states | +2 Àdàkọ:Infobox element/symbol-to-oxidation-state/comment |
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| Electronegativity | Pauling scale: 0.9 |
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| Covalent radius | 221±2 pm |
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| Van der Waals radius | 283 pm |
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Color lines in a spectral rangeSpectral lines of radium |
| Other properties |
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| Natural occurrence | from decay |
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| Crystal structure | (bcc) |
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| Thermal conductivity | 18.6 W/(m·K) |
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| Electrical resistivity | 1 µ Ω·m (at 20 °C) |
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| Magnetic ordering | nonmagnetic |
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| CAS Number | 7440-14-4 |
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| Main isotopes of radium |
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| Isotope |
Abundance |
Half-life (t1/2) |
Decay mode |
Product |
| 223Ra |
trace |
11.43 d |
alpha |
5.99 |
219Rn |
| 224Ra |
trace |
3.6319 d |
alpha |
5.789 |
220Rn |
| 226Ra |
~100% |
1602 y |
alpha |
4.871 |
222Rn |
| 228Ra |
trace |
5.75 y |
beta− |
0.046 |
228Ac |
|
Àdàkọ:Category-inline | references |
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