How many fluorine atoms are required to receive the electrons donated by aluminium during the formation of aluminium fluoride?

Write the chemical formula of the following compounds.

• Sodium oxide
• Aluminium chloride
• Aluminium oxide

Answer the following questions given below related to the chemical formula of aluminium oxide.

• Which are the constituent elements of aluminium oxide?
• What are the valencies of aluminium and oxygen?
• Write the symbols of constituent elements together in such a way that that symbol of the element having lesser electronegativity comes first and then write the chemical formula of aluminium oxide.

Answer the following questions given below related to the chemical formula of carbon dioxide.

• What are the constituent elements in it?
• Write its chemical formula.

Complete the table given below.

Some elements and their valencies are given below. Using these, write the chemical formulae of four compounds.

Complete the table given below and answer the following questions (symbols used are not true).

a) Which element in the table is the most stable one? Justify your answer.
b) Which element donates electrons in a chemical reaction?
c) Write the chemical formula of the compound formed by combining element $\mathrm{S}$ with $\mathrm{P}$.

Electronegativity values of some elements are given. Using these values, find whether the following compounds are ionic or covalent.

(Electronegativity of $\mathrm{Ca}=1, \mathrm{O}=3.5, \mathrm{C}=2.5, \mathrm{S}=2.58, \mathrm{H}=2.2, \mathrm{F}=3.98$)

Sulphur dioxide $\left({\mathrm{SO}}_2\right)$

Water $\left({\mathrm{H}}_2\mathrm{O}\right)$

Calcium fluoride $\left({\mathrm{CaF}}_2\right)$

Carbon dioxide $\left({\mathrm{CO}}_2\right)$