It was discovered in 1894 and it was Argon.
In 1785 Henry Cavendish, an English chemist and physicist, found that air contains a small proportion (slightly less than 1 percent) of a substance that is chemically less active than nitrogen. A century later Lord Rayleigh, an English physicist, isolated from the air a gas that he thought was pure nitrogen, but he found that it was denser than nitrogen that had been prepared by liberating it from its compounds. He reasoned that his aerial nitrogen must contain a small amount of a denser gas. In 1894, Sir William Ramsay, a Scottish chemist, collaborated with Rayleigh in isolating this gas, which proved to be a new element---argon.
for more information: "http://www.britannica.com/EBchecked/topic/416955/noble-gas"
These gases exist only in very low concentration and also are very unreactive.
The noble gases were not included in the original periodic table because they were not discovered until the late 19th century. Once they were discovered, they were added to the periodic table as a separate group due to their unique chemical properties and lack of reactivity with other elements.
No, noble gases were not shown in the periodic table of 1869 because they were not discovered until late 19th and early 20th centuries. Helium was the first noble gas to be discovered in 1895, followed by other noble gases such as neon, argon, krypton, and xenon.
Because noble gases were not discovered when Mendeleev formulated his periodic table
Mendeleev couldn't predict the existence of noble gases because they are inert and do not readily form compounds with other elements. Mendeleev's periodic table was based on the properties of elements and their compounds, and since noble gases do not readily form compounds, they did not fit into his classification scheme.
Layers of gases are present in atmosphere. It was discovered by Mario Molina.
These gases exist only in very low concentration and also are very unreactive.
These gases exist only in very low concentration and also are very unreactive.
Graham
1824
The noble gases were not included in the original periodic table because they were not discovered until the late 19th century. Once they were discovered, they were added to the periodic table as a separate group due to their unique chemical properties and lack of reactivity with other elements.
No, noble gases were not shown in the periodic table of 1869 because they were not discovered until late 19th and early 20th centuries. Helium was the first noble gas to be discovered in 1895, followed by other noble gases such as neon, argon, krypton, and xenon.
Because noble gases were not discovered when Mendeleev formulated his periodic table
Jack Breeze discovered the Noble Gases in 1722, the old bugger
Me.
Noble gases were not discovered then.
Argon was discovered in 1894 by Sir William Ramsay and Lord Rayleigh. They discovered argon while studying atmospheric gases.