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Periodic Table Element Comparison: Compare Elements - Helium vs Actinium

Compare Helium and Actinium

Compare Helium and Actinium on the basis of their properties, attributes and periodic table facts. Compare elements on more than 90 properties. All the elements of similar categories show a lot of similarities and differences in their chemical, atomic, physical properties and uses. These similarities and dissimilarities should be known while we study periodic table elements. You can study the detailed comparison between Helium vs Actinium with most reliable information about their properties, attributes, facts, uses etc. You can compare He vs Ac on more than 90 properties like electronegativity , oxidation state, atomic shells, orbital structure, Electronaffinity, physical states, electrical conductivity and many more.

Facts

Helium
2
He
4.002602
Gas
Colorless
noble gas
18
helium family or neon family 
1
p
1s2
N/A
-268.93 °C
2
CAS7440-59-7
Neighborhood Elements of Helium
Actinium
89
Ac
227
Solid
Silver
actinide
N/A
 
7
f
[Rn] 6d1 7s2
1050 °C
3200 °C
2, 8, 18, 32, 18, 9, 2
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Neighborhood Elements of Actinium

History

History
The element Helium was discovered by Pierre Janssen in year 1895 in Sweden and United Kingdom. Helium derived its name from from the Greek word helios, meaning 'sun'
The element Actinium was discovered by Friedrich Oskar Giesel in year 1899 in France. Actinium derived its name derived its name from from the Greek aktis, 'ray'

Presence: Abundance in Nature and Around Us

Ppb by weight (1ppb =10^-7 %)
0.23
0.23
N/A
5.5×10-7%
7.2×10-10%
N/A
N/A
None
N/A
N/A
N/A
None

Crystal Structure and Atomic Structure

31 pm
22.423540616247 cm3
32 pm
140 pm
0.007
helium Spectrum
424.2, 424.2, 424.2 pm
π/2, π/2, π/2
Fm_ 3m
225

Face Centered Cubic

helium Crystal Structure
195 pm
22.542204568024 cm3
N/A
N/A
810
actinium Spectrum
567, 567, 567 pm
π/2, π/2, π/2
Fm_ 3m
225

Face Centered Cubic

actinium Crystal Structure

Atomic and Orbital Properties

Atomic Number
Number of Electrons (with no charge)
Number of Protons
Mass Number
Number of Neutrons
Shell structure (Electrons per energy level)
Electron Configuration
Valence Electrons
Oxidation State
Atomic Term Symbol (Quantum Numbers)
Shell structure
2
2
2
4.002602
2.002602
2
1s2
1s2
 
1S0
helium Shells
89
89
89
227
138
2, 8, 18, 32, 18, 9, 2
[Rn] 6d1 7s2
6d1 7s2
 3
2D3/2
actinium Shells

Isotopes - Nuclear Properties

Isotopes
Naturally occurring stable isotopes:
3He, 4He.
Naturally occurring stable isotopes:
None.

Chemical Properties: Ionization Energies and electron affinity

0
N/A
0 kJ/mol
2372.3, 5250.5 kJ/mol
3
1.1
N/A
499, 1170 kJ/mol

Physical Properties

0.1785 g/l
22.423540616247

 

N/A
N/A
N/A
N/A


 

N/A
N/A
N/A

 

N/A
N/A
N/A

 

0.1513 W/(m K)
N/A

 

Diamagnetic
N/A
-5.9×10-9
-2.36×10-11
-1.05×10-9

 

1.000035

 

970 m/s
10.07 g/cm3
22.542204568024

 

N/A
N/A
N/A
N/A


 

N/A
N/A
N/A

 

N/A
N/A
N/A

 

12 W/(m K)
N/A

 

N/A
N/A
N/A
N/A
N/A

 

N/A

 

N/A

Thermal Properties - Enthalpies and thermodynamics

N/A
-268.93 °C
5.19 K
N/A

 

0.02 kJ/mol
0.083 kJ/mol
N/A
1050 °C
3200 °C
N/A
N/A

 

14 kJ/mol
400 kJ/mol
N/A

Regulatory and Health - Health and Safety Parameters and Guidelines

CAS7440-59-7
RTECSMH6520000
2.2
1963
N/A
0
N/A
1
0

 

N/A
N/A
CAS7440-34-8
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A

 

N/A
N/A