Question

Give two examples of gaseous elements.

Answer 1

Hint: The elements which are gases at standard temperature and pressure are known as gaseous elements. 11 gaseous elements are there in the periodic table.

Complete answer:
Gases have low density as compared to other two states of matter i.e. solid and liquid. These are highly compressible and have no definite shape or volume because the intermolecular forces between the gas particles are very weak. Gaseous elements are those elements which belong to the gaseous state of matter i.e. these elements are gaseous in nature. There are 11 elements of gaseous elements present in the periodic table out of which mostly are present on the right side of the periodic table except hydrogen and the gases present in the 18th group of periodic table are known as noble gases and exist as monatomic gases whereas the other gaseous elements are diatomic molecules (\[{{H}_{2}},{{N}_{2}},{{O}_{2}},{{F}_{2}}\] and \[C{{l}_{2}}\]).
Oxygen can also form a second allotrope called the highly reactive triatomic molecule ozone\[({{O}_{3}})\], which is also a gas.
All the gaseous elements contain covalent or polar covalent bonds and termed as nonpolar or polar molecules.
Two main example of gaseous state are:
Hydrogen: It is the only gas present on the left side of the periodic table and represented by H. It is colorless, odorless and has the density lower than all other gases. There are many uses of hydrogen gas like in combustion engines and fuel cell electric vehicles, used to break down crude oil into fuel oil, gasoline and in the production of petroleum products. Hydrogen is essential for the production of ammonia for use in fertilizer making and is used as a hydrogenating agent for polyunsaturated fats.
Helium: It is the first member of the noble gas family and represented by He. Noble gases are those whose outermost electron shell is complete as He has atomic number 2 so its configuration is written as \[1{{s}^{2}}\] and shell (K = 2) which is completely filled. It is colorless, odorless and tasteless gas. Helium gas is used in altitudes research and meteorological balloons, as an inert protective gas in welding, in the production of germanium crystals and silicon crystals. It has the ability to diffuse through solids much faster than air so it is used industrially for pipeline leak detection.

Note:
Gaseous elements are generally those substances which exist in a third state of matter i.e. in a gaseous state whose particles are arranged in a free manner that they don’t have any particular shape or volume. There are 11 gaseous elements present in the periodic table out of which we discuss Hydrogen and helium gas.