Chemical compounds

…..elements are the most stable elements

• Metals
• Non-metals
• Nobel gases
• Metaloids

All of the folowing elements are monovalent except …..

• hydrogen
• sodium
• oxygen
• chlorine

All the following are divalent except…

When an atom loses,gains or shares with one electron, whose valency is…

• monovalent
• divalent
• trivalent
• tetravalent

When an atom gains or shares by two electron, its valency will be…

• monovalent
• divalent
• trivalent
• tetravalent

The valency of ferrous is ….

• monovalent
• divalent
• trivalent
• tetravalent

All of the following are nonmetals having more than one valency,except…

• copper
• phosphorus
• sulpher
• nitrogen

The valency of argon (18Ar) is….

• trivalent
• divalent
• monovalent
• zero

In trivalent elements, the outermost energy level contains….electrons

• (3) or (5)
• (5) or (6)
• (7) or (1)
• (6) or (3)

The valency of copper in (Cu₂O) is …..

• monovalent

• divalent

• trivalent

• tetravalent