Hydrogen Gas Formula – Chemical Formula of Hydrogen Gas

Hydrogen is a colorless, odorless, tasteless, and flammable gas. The formula for hydrogen gas, H₂, indicates that it typically exists as a diatomic molecule. Each hydrogen molecule consists of two atoms. An individual hydrogen atom comprises a nucleus with one proton carrying a positive electrical charge and one electron carrying a negative electrical charge. Under normal conditions, hydrogen gas is a collection of these diatomic hydrogen molecules. Learn more about hydrogen gas, its formula and properties in this article prepared by Extramarks.

What is Hydrogen Gas?

Hydrogen gas, composed of two hydrogen atoms, is the lightest element in Group 1 of the periodic table. It is colorless, odorless, and tasteless, represented by the symbol H and an atomic number of 1. Under standard conditions, hydrogen forms diatomic molecules with the formula H₂. Known as molecular hydrogen, it is a clean-burning fuel produced from coal and water. Hydrogen gas can be stored either as a compressed gas or a liquid and is utilized in the manufacturing polyurethane plastics. Additionally, it is suitable for powering internal combustion engines in vehicles.

Hydrogen Gas Chemical Formula

Hydrogen gas exists as diatomic molecules, meaning it is composed of two hydrogen atoms bonded together. Its chemical formula is H₂. In each H₂ molecule, the two hydrogen atoms share electrons, forming a stable bond.

Hydrogen Gas Structural Formula

​The structure of a hydrogen gas molecule (H₂) is simple. It is made up of two hydrogen atoms bonded together. These two atoms share electrons, forming a covalent bond that results in a stable diatomic molecule. This structure is commonly depicted as H-H, with the line between the “H” symbols indicating the covalent bond.

Hydrogen Gas Formula Molar Mass

The chemical formula for hydrogen gas is H₂. Its molar mass, calculated by summing the atomic masses of its two hydrogen atoms, is approximately 2.016 grams per mole.

Hydrogen Gas Formula Charge

Hydrogen gas (H₂) is electrically neutral, meaning it has no net electrical charge. Each hydrogen atom within the molecule contains one proton and one electron. When two hydrogen atoms combine to form H₂, the total number of protons equals the total number of electrons, resulting in an overall neutral charge.

Preparation of Hydrogen Gas

To produce hydrogen gas, you can react zinc with hydrochloric acid, yielding hydrogen gas and zinc chloride:

Zn+2HCl→ZnCl₂ +H₂

​Alternatively, you can generate hydrogen gas by reacting zinc with sulfuric acid, which results in the formation of zinc sulfate and hydrogen gas:

Zn+H₂SO₄→ZnSO₄ +H₂

Physical Properties of Hydrogen Gas

• Hydrogen gas is a colorless and odorless substance. 
• Its molecular weight is 1.00794. 
• The density of hydrogen gas is 0.0893 g/L. 
• It has a melting point of -259.2°C and a boiling point of -252.9°C. 
• The solubility of hydrogen gas in water is 1.62 mg/L at 21°C.

Chemical Properties of Hydrogen Gas

Hydrogen gas participates in a variety of chemical reactions.

• It reacts with nitrogen in the atmosphere to produce ammonia:

N₂ +3H₂ → 2NH₃

• ​In methanol production, hydrogen gas is used and remains mixed with the synthesis gas stream:

CO + 2H₂ → CH₃OH

• ​When combined with chlorine, hydrogen forms hydrogen chloride (HCl):

H2 + Cl₂ → 2HCl

• ​Under certain temperature and pressure conditions, hydrogen gas can reduce metal oxides and metallic salts to metals:

H₂ + FeO→Fe + H₂O

• Hydrogen gas can also react with PdCl₂ to produce palladium and hydrogen chloride:

H₂ + PdCl₂ → Pd + 2HCl

Uses of Hydrogen Gas

Hydrogen gas has various applications:

• It is used along with helium gas in equal volumes to fill weather observation balloons.
• It powers internal combustion engines in automobiles.
• The oxy-hydrogen flame, known for generating intense heat, is employed in welding and cutting metals.
• It is utilized in converting edible vegetable oils into Vanaspati ghee.
• Hydrogen gas is involved in the production of polyurethane plastics

FAQs on Hydrogen Gas Chemical Formula

1. Is hydrogen gas H2 or H?

Hydrogen gas is H2. It exists as a diatomic molecule, meaning two hydrogen atoms bond together to form a single molecule of hydrogen gas.

2. What is the formula for hydrogen as a gas?

The formula for hydrogen as a gas is H2. This indicates that hydrogen gas consists of two hydrogen atoms bonded together.

3. Why is H2 a gas?

H2 is a gas because hydrogen molecules (H2) are very light and move rapidly at room temperature, causing them to exist in a gaseous state under standard conditions.

4. What is hydrogen’s general formula?

The general formula for molecular hydrogen in its natural, gaseous state is H2. This represents the diatomic nature of hydrogen gas, where two hydrogen atoms are bonded together.