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Periodic Table Element Comparison: Compare Elements - Hydrogen vs Helium

Compare Hydrogen and Helium

Compare Hydrogen and Helium 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 Hydrogen vs Helium with most reliable information about their properties, attributes, facts, uses etc. You can compare H vs He on more than 90 properties like electronegativity , oxidation state, atomic shells, orbital structure, Electronaffinity, physical states, electrical conductivity and many more.

Facts

Hydrogen
1
H
1.00794
Gas
Colorless
other nonmetal
1
lithium family 
1
s
1s1
-259.14 °C
-252.87 °C
1
CAS1333-74-0
Neighborhood Elements of Hydrogen
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

History

History
The element Hydrogen was discovered by Henry Cavendish in year 1766 in United Kingdom. Hydrogen derived its name from from the Greek elements hydro- and -gen meaning 'water-forming'
The element Helium was discovered by Pierre Janssen in year 1895 in Sweden and United Kingdom. Helium derived its name derived its name from from the Greek word helios, meaning 'sun'

Presence: Abundance in Nature and Around Us

Ppb by weight (1ppb =10^-7 %)
0.75
0.75
0.024
0.0015
0.11
0.1
0.23
0.23
N/A
5.5×10-7%
7.2×10-10%
N/A

Crystal Structure and Atomic Structure

53 pm
11.211790878754 cm3
37 pm
120 pm
0.332
hydrogen Spectrum
470 pm, 470 pm, 340 pm
π/2, π/2, 2 π/3
P63/mmc
194

Simple Hexagonal

hydrogen Crystal 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

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
1
1
1
1.00794
0.0079400000000001
1
1s1
1s1
-1  1
2S1/2
hydrogen Shells
2
2
2
4.002602
2.002602
2
1s2
1s2
 
1S0
helium Shells

Isotopes - Nuclear Properties

Isotopes
Naturally occurring stable isotopes:
1H, 2H.
Naturally occurring stable isotopes:
3He, 4He.

Chemical Properties: Ionization Energies and electron affinity

1
2.2
72.8 kJ/mol
1312 kJ/mol
0
N/A
0 kJ/mol
2372.3, 5250.5 kJ/mol

Physical Properties

0.0899 g/l
11.211790878754

 

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


 

N/A
N/A
N/A

 

N/A
N/A
N/A

 

0.1805 W/(m K)
N/A

 

Diamagnetic
N/A
-2.48×10-8
-4.999×10-11
-2.23×10-9

 

1.000132

 

1270 m/s
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

Thermal Properties - Enthalpies and thermodynamics

-259.14 °C
-252.87 °C
32.97 K
N/A

 

0.558 kJ/mol
0.452 kJ/mol
N/A
N/A
-268.93 °C
5.19 K
N/A

 

0.02 kJ/mol
0.083 kJ/mol
N/A

Regulatory and Health - Health and Safety Parameters and Guidelines

CAS1333-74-0
RTECSMW8900000
2.1
1966
N/A
4
N/A
3
0

 

535.5 °C
-18 °C
CAS7440-59-7
RTECSMH6520000
2.2
1963
N/A
0
N/A
1
0

 

N/A
N/A