Page 34 - ICSE Chemistry 6

Symbols of some common elements are given in Table 2.1–2.3
Table 2.1: Symbols of Elements Derived from First Le er of their Names
Elements Symbols Elements Symbols Elements Symbols Elements Symbols

Hydrogen H Boron B Carbon C Nitrogen N
Oxygen O Fluorine F Phosphorous P Sulphur S

Table 2.2: Symbols of Elements Derived from Two Le ers of their Names

Elements Symbols Elements Symbols Elements Symbols Elements Symbols
Helium He Lithium Li Beryllium Be Neon Ne
Magnesium Mg Aluminium Al Silicon Si Chlorine Cl

Argon Ar Calcium Ca

Table 2.3: Symbols of Elements Derived from their La n Names
Elements Symbols Elements Symbols Elements Symbols

Sodium (Natrium) Na Potassium (Kalium) K Iron (Ferrum) Fe
Copper (Cuprum) Cu Silver (Argentum) Ag Gold (Aurum) Au
Lead (Plumbum) Pb

COMPOUNDS

Many elements have the tendency to combine with
each other and form compounds.
A compound is a pure substance formed by the
chemical combina on of two or more elements in
a defi nite propor on by mass. For example, sodium
chloride or common salt is a compound made of two sodium chloride water
elements—sodium and chlorine. It can be broken Fig. 2.6: Compounds
down into these two elements.

Table 2.4: Some Common Compounds
Compound Elements present

Ammonia Nitrogen, hydrogen
Carbon dioxide Carbon, oxygen
Common salt Sodium, chlorine
Sand Silicon, oxygen

Sodium hydroxide Sodium, oxygen, hydrogen
Water Hydrogen, oxygen

Characteristics of a Compound

• A compound is made up of two or more elements.

20