______________ react with water to form strong alkalies.
Halogens
Noble gases
Boron
Alkali metals
_________________ lie at the bottom of the periodic table in two horizontal rows.
Transition elements
Inner transition elements
Post transition elements
________________ are univalent.
Alkaline earth metals
__________arranged elements in increasing order of atomic weights in groups of three called triads.
Newland
Dobereiner
Mendeleev
Moseley
Each period begins with an element having _______________ electron in the outermost shell.
1
3
5
7
________arranged elements in increasing order of atomic weights in series of eight.
According to modern periodic law, the physical and chemical properties of elements are periodic functions of their
Atomic number
Atomic weight
Valency
Density
First group elements are commonly known as
Lanthanides
The properties which repeat themselves at regular intervals are called
Periodic properties
Alternate properties
Gaseous properties
Physical properties
_______________ is the distance between the centre of the nucleus and the outermost shell.
Ionisation potential
Atomic radius
Electron affinity
Electronegativity
