|
|
ନାମ, ପ୍ରତୀକ | radium, Ra |
---|
Appearance | silvery white metallic |
---|
ଉଚ୍ଚାରଣ | RAY-dee-əm |
---|
|
|
ପରମାଣୁ କ୍ରମାଙ୍କ (Z) | 88 |
---|
ଶ୍ରେଣୀ, ବ୍ଳକ | group 2 (alkaline earth metals), s-block |
---|
ପର୍ଯ୍ୟାୟ | period 7 |
---|
ମୌଳିକ ପ୍ରକାର | alkaline earth metal |
---|
ମାନକ ପରମାଣବିକ ଓଜନ (Ar) | (226) |
---|
ଇଲେକ୍ଟ୍ରୋନ୍ ବିନ୍ୟାସ | [Rn] 7s2 |
---|
per shell | 2, 8, 18, 32, 18, 8, 2 |
---|
|
ଅବସ୍ଥା | solid |
---|
ଗଳନାଙ୍କ | 973 K (700 °C, 1292 °F) |
---|
ସ୍ଫୁଟନାଙ୍କ | 2010 K (1737 °C, 3158.6 °F) |
---|
Density near r.t. | 5.5 g/cm3 |
---|
Heat of fusion | 8.5 kJ/mol |
---|
Heat of | 113 kJ/mol |
---|
pressure
P (Pa)
|
1
|
10
|
100
|
1 k
|
10 k
|
100 k
|
at T (K)
|
819
|
906
|
1037
|
1209
|
1446
|
1799
| |
|
Oxidation states | 2 (strongly basic oxide) |
---|
Electronegativity | Pauling scale: 0.9 |
---|
Covalent radius | 221±2 pm |
---|
Van der Waals radius | 283 pm |
---|
|
Crystal structure | body-centered cubic (bcc) |
---|
Thermal conductivity | 18.6 W/(m·K) |
---|
Electrical resistivity | 1 µ Ω·m (at 20 °C) |
---|
Magnetic ordering | nonmagnetic |
---|
CAS Number | 7440-14-4 |
---|
|
ଆବିଷ୍କାର | Pierre Curie and Marie Curie (1898) |
---|
First isolation | Marie Curie (1902) |
---|
|
|
| references |