MOLE CONCEPT
(part 1)(Basics only)
Atomic Mass
It is 1/12th the mass of a C-12 atom.
It is denoted by:
u (unified mass)
amu(atomic mass unit)
da(Dalton)
also 1u=1amu=1da
VALUE OF 1 AMU (on conventional scale)
( 12th
1
)∗mass of 1C−12 atom
Mass of 1 C-12 atom=1.99∗10 g −23
Therefore 1 amu=( 12 )∗1.99∗10 g
1 −23
, 1 amu=1.66∗10 g −24
Also 1 amu= NA
1
Where NA=Avogardo’s no
NA=6.022∗10 23
1
1 amu=
6.022∗1023
RELATIVE ATOMIC MASS(R.A.M)
It tells how many times one atom of an element is
heavier than 1/12th the mass of aC-12 atom
mass of 1 atom of an element
RAM of an element (on conventional scale)=
1 amu
mass of 1 atom of atom=total no of nucleons∗mass of 1 nucleon
Also mass of 1 C-12 atom=( 121 )∗12∗mass of 1 nucleon
Let’s denote 1 nucleon by n
So RELATIVE ATOMIC MASS COULD BE
WRITTEN As
(part 1)(Basics only)
Atomic Mass
It is 1/12th the mass of a C-12 atom.
It is denoted by:
u (unified mass)
amu(atomic mass unit)
da(Dalton)
also 1u=1amu=1da
VALUE OF 1 AMU (on conventional scale)
( 12th
1
)∗mass of 1C−12 atom
Mass of 1 C-12 atom=1.99∗10 g −23
Therefore 1 amu=( 12 )∗1.99∗10 g
1 −23
, 1 amu=1.66∗10 g −24
Also 1 amu= NA
1
Where NA=Avogardo’s no
NA=6.022∗10 23
1
1 amu=
6.022∗1023
RELATIVE ATOMIC MASS(R.A.M)
It tells how many times one atom of an element is
heavier than 1/12th the mass of aC-12 atom
mass of 1 atom of an element
RAM of an element (on conventional scale)=
1 amu
mass of 1 atom of atom=total no of nucleons∗mass of 1 nucleon
Also mass of 1 C-12 atom=( 121 )∗12∗mass of 1 nucleon
Let’s denote 1 nucleon by n
So RELATIVE ATOMIC MASS COULD BE
WRITTEN As
