Periodic Classification of Elements
_______periodic table had some discrepancies, which were difficult to overcome.
Hendry Moseley, a British scientist in 1912, discovered a new property of elements called ____
The physical and chemical properties of the ____ are the periodic functions of their atomic numbers
The horizontal rows are called ____
There are _____ periods in the periodic table.
_____is the shortest period. It contains only two elements (Hydrogen and Helium).
Second period contains ____ elements
Third period contains ____ elements
Fourth period contains ____ elements
Fifth period contains ____ elements
Sixth period contains _____ elements
Seventh period contains _____ elements
The vertical columns in the periodic table starting from top to bottom are called
_______
There are ____ groups in the periodic table.
The Lanthanides and Actinides, which form part of Group 3 are called ____
Except ______ all the elements present in each group have the same number of electrons in their valence shell and thus have the same valency
Anything which repeats itself after a regular interval is called _____
Properties such as atomic radius, ionic radius, ionisation energy, electronegativity, electron affinity, show a regular periodicity and hence they are called _______
______ of an atom is defined as the distance between the centre of its nucleus
and the outermost shell containing the valence electron
Atomic radius in metal atoms is known as _____
In non-metallic elements, their atomic radius is known as ______
_________ is defined as the distance from the centre of the nucleus of the ion upto the point where
it exerts its influence on the electron cloud of the ion
When a neutral atom loses an electron, it becomes a positively
charged ion called_____
The gain of an electron by a neutral atom forms a negatively
charged ion called_____
_________ is the minimum energy required to remove an electron from
an isolated gaseous atom in its ground state to form a cation
Ionisation energy otherwise called ______ ionisation
_______energy decreases down the group in the periodic table.
________ is a science of extracting metals from their ores and modifying the
metals into alloys for various use
______is the process of removal of impuries from the ore.
______ is the convertion of the ore into metal.
____is the process of purification of the metal.
A ____ may be a single compound or a complex mixture of various
compounds of metals found in the Earth
The mineral from which a metal can be readily and economically extracted on a
large scale is said to be an ___
The process of extracting the ores from the Earth’s crust is called ____
The rocky impurity associated with an ore is called ____
___is the substance added to the ore to reduce the fusion temperature and to
remove the impurities
____ is the fusible product formed when a flux reacts with a gangue during the
extraction of metals.
______ is the process of reducing the roasted metallic oxide from the
metal in its molten condition
All metals are solids at room temperature except ____
____ are good conductors of heat and electricity
The molten matte is transferred to Bessemer converter in order to
obtain___
____is used in making pipes, stoves, radiators, railings, manhole covers and drain pipes
____ is used in the construction of buildings, machinery, transmission cables and T.V towers and in
making alloy
_____is used in making springs, anchors and electromagnets.
_____ is a homogeneous mixture of two or more metals or of one or more metals with
certain non-metallic elements.
_____ is an alloy of mercury with another metal
_____is the gradual destruction of metals by chemical or electrochemical reaction with
the environment.
The metals can be ____ to prevent from the process of corrosion. E.g: Stainless Steel
_____ is the process of coating zinc on iron sheets by using electric current
_____is a method of coating one metal over another metal by passing
electric current
____ is widely used for anodizing process.
____ is the method of controlling corrosion of a metal surface protected is coated with the metal which is easily corrodible.