Properties of Groups with Examples
Properties of Groups with Examples
a) I A Alkaline Metals:
Except from 1H, all elements in this group are metal. They,
- have one electron on outer shells
- have tendency to lose one electron in outer shells and become +1 ion
- are very reactive and exist in compounds
- are good conductors of electricity and heat
- all compounds of them are soluble in water
- have lower ionization energy than other elements in same period
- are very soft and melting points of them are low.
1H, 3Li, 11Na, 19K, 37Rb, 55Cs, 87Fr
b) II A Alkaline Earth Metals:
All elements in this group are metal. They
- have two electrons on outer shells
- have tendency to lose two electrons in outer shells and become +2 ion
- are good conductors of electricity and heat in solid and liquid phases
- are reactive and exist in compounds
- have higher ionization energy than alkaline metals
4Be, 12Mg, 20Ca, 38Sr, 56Ba, 88Ra
c) VII A Halogens:
All elements in this group are nonmetals.
- have seven electrons on outer shells, thus they can have values changing between +7 and -1 in compounds
- if they are in metal-nonmetal compounds they have -1 value
- they exist in diatomic molecules like F2, Br2
- they can exist in solid, liquid and gas phase in normal conditions
- compounds with hydrogen are acidic
- have higher tendency to bond electron and becomes -1 ion
9F, 17Cl, 35Br, 53I, and 85At
d) VIII A Noble Gases:
- have eight electrons on outer shells
- electron configurations end with ns2np6
- Noble gases are most stable elements and do not form compounds with other elements and each other.
- In normal conditions they exist in gas phase
- Melting and boiling points are lower than other group elements
- Ionization energies of them are higher than other group elements in same period
2He, 10Ne, 18Ar, 36Kr, 54Xe, 86Rn
Properties of Transition Metals
- they are called also heavy metals
- All of them are metal
- They can have different + values like; Fe+2 and Fe+3
Example: Which one of the statements given below for X element are true?
X + H2O → XOH + 1/2H2
I. X is in IA group
II. X is alkaline metal
III. X is noble gas
Since X has +1 value in compound, it is in IA group so alkaline metal. I and II are true.
III is false