Properties of Hydrogen Name origin: Greek words hydro (water) and gen (generate) Atomic Number : 1 Atomic Weight : 1.0079 Melting Point: -259°C Boiling Point: - 253°C Vapour Density: 0.08376 kg/m3( at 20°C,1atm) Specific Gravity : 0.0696 Flashpoint : –253 °C Valence:  1 Hydrogen is a colourless, odourless, combustible gas.

Hydrogen Facts Hydrogen is the simplest and most

abundant element in the universe It is estimated that 90% of the visible

universe is composed of hydrogen.

Hydrogen Production U.S. production: 3 billion cubic feet per year.

Hydrogen is prepared by: steam on heated carbon. decomposition of certain hydrocarbons with heat. reaction of sodium or potassium hydroxide on aluminum. electrolysis of water. displacement from acids by certain metals.

Uses of Hydrogen Pure hydrogen is a gas, but it is barely found in our

atmosphere Hydrogen occurs primarily in combination with

oxygen in water Its also present in organic matter such as living plants,

petroleum, coal, etc. Hydrogen is the lightest element, so it can combine

with all other elements -- sometimes explosively -- to form compounds.

Large amounts of hydrogen are combined with nitrogen from the air to produce ammonia (NH3) through a process called the Haber process.

Hydrogen is also added to fats and oils, such as peanut oil, through a process called hydrogenation.

Uses of Hydrogen: Fuel There is an estimated 400 to 500 hydrogen-fueled vehicles

in the U.S. Mostly in California

Most of these vehicles are buses and automobiles powered by electric motors They store hydrogen gas or liquid on board and convert the hydrogen

into electricity for the motor using a fuel cell Only a few of these vehicles burn the hydrogen directly (producing

almost no pollution). The present cost of fuel cell vehicles greatly exceeds that of

conventional vehicles in large part due to the expense of producing fuel cells

Liquid hydrogen is used in the study of superconductors and, when combined with liquid oxygen, makes an excellent rocket fuel.

Hydrogen sharing for H2O

H2O

 

                       

Hydrogen Isotopes Hydrogen has three common isotopes. The simplest isotope, called protium, is

just ordinary hydrogen. The second is a stable isotope called

deuterium.Discovered in 1932

The third isotope is called tritium.Discovered in 1934

References: http://darkwing.uoregon.edu/~ch111/L12.

htm>. www.eia.doe.gov/kids/energyfacts/sourc

es/IntermediateHydrogen.html http://periodic.lanl.gov/elements/1.html.