Қуаныш Ағай
Inst: @mezhdunamihimia
Atomic structure. Isotopes.
ATOM
NUCLEUS – ядро
1-task: Find the p,n,e numbers of given atoms
Isotopes – same atomic number, different atomic mass
Isobars – same atomic mass, different atomic number
Isotons – same neutron numbers, different atomic number
2-task: find the isotopes, isobars and isotons
Қуаныш Ағай
14
C6 ,
30
U92,
O8 – are
31
C6 ,13C6
235
16
N7 ,
Si14 ,
12
Inst: @mezhdunamihimia
15
P15 ,
,
32
S16 – are
14
C6 – are
235
Np93,
235
Pu94 – are
3-task: calculate the related atomic mass of isotopes
1. Isotopes of carbon in nature:
C
12
– 98.892%
(12 * 98.892%/100%) + (13 * 1.108/100%) = (12 * 0.98892)
+ (13 * 0.01108) =
C
13
– 1.108%
=
11.86704 + 0.14404 = 12.01108 g/mole
2. In nature, lithium occurs in the form of such isotopes:
Li
7
– 92.7%
Li
6
– 7.3%
3. Chlorine isotopes according to distribution in nature:
Cl
37
– 24.47%
Cl
35
– 75.53%
4. Natural magnesium isotopes: 24Mg, 25Mg, 26Mg. Calculate the average atomic
mass of natural magnesium if the atomic percentages of the individual isotopes
are 78.6%, 10.1%, and 11.3%, respectively.
5. Calculate the average atomic mass of gallium if,
69Ga
64%,
71Ga
– 36%