# Helium Element

Find elemental, thermodynamic, material, electromagnetic, atomic & nuclear properties of helium element along with reactivity and abundance.

Sarah Taylor-

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Helium is the second element in the periodic table. A periodic table contains 118 elements distributed in 7 rows and 18 columns. The rows are known as periods and the columns are the groups of the periodic table. The elements of the periodic table are arranged according to their atomic number.

## Basic elemental properties of Helium atom

There are 118 different elements in the periodic table but there are some basic elemental properties of each. In a periodic table, elements with basic elemental properties are grouped together. Basic elemental properties of Helium are:

### Atomic Symbol of Helium element

Every element in the periodic table has its atomic symbol or chemical symbol for representation. The atomic symbol of Helium is “He”

### Atomic Number of Helium

Elements in the periodic table are arranged in groups and periods on the basis of their atomic number.

Atomic number is the number of protons present in the nucleus of an atom. The atomic number of Helium is 2. This shows Helium is the second element of the periodic table.

### Short Electronic Configuration of Helium atom

Short Electronic Configuration of Helium is 1s2

### Block of Helium in Periodic Table

There are four blocks (s, p, d, f) in the periodic table. Helium belongs to the s-block of the periodic table. S block is also the first block in the periodic table.

### Group of Helium element in Periodic Table

Groups are the columns of the periodic table and Helium belongs to the 18th group.

### Period of Helium in Periodic Table

Periodic table is arranged in periods and groups. The rows going across left to right are periods and Helium atom is placed in the first period. Elements that are present in a period share common properties .

### Atomic Mass of Helium

Atomic mass is the mass of an atom and the atomic mass of Helium is 4.002602 u. If we round off the atomic mass of Helium to 3 decimal points, we get 4.003 u.

## Thermodynamic properties of Helium

Thermodynamic properties are the characteristic features of a system, capable of specifying the system's state. The thermodynamic properties of an element include chemical, physical and thermal properties. The thermodynamic properties of Helium are:

### Phase at STP

Phase at STP is the state in which an element is present. The stp phase of Helium is “Gas”.

### Melting Point of Helium

Melting point is a temperature at which an element of substance changes its state from solid to liquid. The melting point of Helium gas is -272.2 °C.

### Boiling Point of Helium element

A boiling point is a temperature at which an element of a substance starts turning into vapors. The boiling point of Helium gas is -268.93 °C.

### Critical Temperature of Helium atom

A critical temperature is a point at which a gas cannot become liquid even if we are applying pressure. The critical temperature of Helium gas is 5.19 K.

### Critical Pressure of Helium

The critical pressure required to liquefy a gas at its critical temperature. The critical pressure of Helium gas is 0.227 MPa.

### Molar Heat of Fusion of Helium

Molar Heat of Fusion is the energy required to melt each mole of substance. The molar heat of fusion of Helium is 0.02 kJ/mol.

### Molar heat of Vaporization

The Molar heat of vaporization is the heat absorbed by the one specific mole of a substance. The molar heat of vaporization of Helium gas is 0.083 kJ/mol or 0.08 kJ/mol.

### Specific heat at STP

The specific heat of Helium at STP is 5193.1 J(kgK).

### Adiabatic Index of Helium element

The adiabatic index is the ratio of specific heats of pressure and constant volume. The adiabatic index of Helium is 5/3.

These are some of the main thermodynamic properties of Helium. Let’s find out all the material properties of Helium.

## Material properties of Helium atom

We have discussed basic elemental properties and thermodynamic properties of Helium gas. Besides these, there are many material properties of Helium as well. Some of the material properties include density, molar volume, refractive index and thermal conductivity.

### Density of Helium

The density of Helium is 1.785x10-4 g/cm3

### Molar Volume of Helium

The molar volume of Helium is 22420 cm3/mol

### Refractive Index of Helium

The refractive Index of Helium is 1.000035

### Sound Speed of Helium

The sound speed of Helium is 970 m/s

### Thermal Conductivity of Helium

The thermal conductivity of Helium is 0.1513 W/(mK)

These are the main material properties of Helium.

## Electromagnetic properties of Helium

When there is any emission or absorption of electromagnetic radiations, a martial responds to these changes. All elements of a periodic table have electromagnetic properties. Some of the main electromagnetic properties of Helium gas include magnetic types, magnetic volume, mass magnetic susceptibility and color.

### Magnetic type of Helium

The magnetic type Helium refers to the fact that it is diamagnetic.

### Volume Magnetic Susceptibility of Helium

The volume magnetic susceptibility of Helium is -1.05 x 10-9

### Mass Magnetic Susceptibility of Helium

The mass magnetic susceptibility of Helium is -5.9 x 10-9 m3 /kg

### Molar Magnetic Susceptibility of Helium

The molar magnetic susceptibility of Helium gas is -2.36 x 10-11 m3 /mol

### Color of Helium Gas

The Helium gas is invisible or colorless.

These are some of the main electromagnetic properties of Helium gas.

## Reactivity of Helium

### Valency of Helium

The valency of an element is a number that represents the ability of an atom to combine with other atoms. The valency of Helium is 0.

### Electronegativity of Helium

Electronegativity of Helium is the tendency of its atom participating in a covalent bond to attract the bonding electrons. The helium has no electronegativity because it is a noble gas.

### Electron affinity of Helium element

Electron affinity is the energy released when one electron is added to a neutral atom to form an anion. The electron affinity of Helium is 0 kJ/mol

### First ionization energy of Helium

It is the energy to remove the outermost electron from the neutral atom in the gas phase. The first ionization energy of Helium is 2372.3 kJ/mol.

## Atomic properties

Term Symbol of Helium

The term symbol specifies the electronic state of an atom. The term symbol of Helium atom is 1 S 0.

### Atomic Radius of Helium element

The total distance from an atom's nucleus to the outermost orbital of an electron is its atomic radius. The atomic radius of Helium is 31 pm.

Covalent radius is the measurement of an atom's size that forms one covalent bond. The covalent bond of Helium is 28 pm.

### Van der Waals Radius of Helium

Van der waals radius is the measurement for the size of an atom that is not chemically bonded. The van der waals radius of Helium element is 140 pm.

## Abundances of Helium

It is the measure that tells us about the percentage of which it is present.

### Abundance of Helium in the universe

The abundance of Helium in the universe is 23 mass %

### Abundance of Helium in the solar system

The abundance of Helium in the solar system is 23 mass %.

### Abundance of Helium in earth's crust

The abundance of Helium in earth's crust is 5.5 x 10 -7 mass %.

### Abundance of Helium in ocean

The abundance of Helium in the ocean is 7.2 x 10 -10 mass %.

### Universe Molar Abundances of Helium

The universe molar abundances of Helium is 7.2 mol %

### Solar Molar Abundances of Helium

The solar molar abundances of Helium is 7.4 mol %

### Ocean Molar Abundances of Helium

The ocean molar abundances of Helium is 1.1 x 10-9 mol %

### Crust Molar Abundances of Helium

The crust molar abundances of Helium is 3 x 10-6 mol %.

## Nuclear properties of Helium

### Half life of Helium

Half life is the time for the radioactivity of a specified isotope to fall to half its original value. The half Life of Helium is stable.

### Stable isotopes of Helium

Stable isotopes of Helium are 4He (99.999863%) | 3He (1.37x10-4%)

### Nuclear Spin of Helium

Nuclear spin of Helium is 3He ½+ | 4He 0+

### Unstable isotopes of Helium

Unstable isotopes of Helium is 6He (806.7 ms)

### Neutron Cross Section of Helium

The neutron cross section of Helium is 0.007 b.

### Neutron Mass Absorption of Helium

The neutron mass absorption of Helium is 1 x 10-5m2 /kg.

## Identifiers of Helium

### CAS Number of Helium

The CAS number of Helium is 7440-59-7.

### PubChem CID number of Helium

The PubChem CID number of Helium is 23987

### Is helium a pure substance?

Yes, helium is a pure substance because we cannot separate it into different other matters by all physical means.

### Is helium bad for you?

Helium is a chemical element and it can be bad for you. It directly impacts our breathing and cuts off the oxygen. Breathing in pure helium can lead you to hypoxemia and it can be fatal.

### Is the helium flammable?

Helium is non-flammable and that is why the party balloons are filled with this gas.