Q99P - Chemistry: Molecular Nature Of Matter And Change

Question

Give the formula of compounds in each set

1. Lead(II) oxide and lead(IV) oxide;
2. lithium nitride, lithium nitrite, and lithium nitrate;
3. strontium hydride and strontium hydroxide;
4. magnesium oxide and manganese(II) oxide.

Step-by-Step Solution

Answer

a. Lead oxide is  $\mathbf{PbO}$

    Lead(IV) oxide is  ${\mathbf{PbO}}_{\mathbf{2}}$

b. Lithium nitride is  ${\mathbf{Li}}_{\mathbf{3}}\mathbf{N}$

    Lithium nitrite is  ${\mathbf{LiNO}}_{\mathbf{2}}$

    Lithium nitrate is  ${\mathbf{LiNO}}_{\mathbf{3}}$

c. Strontium hydride is ${\mathbf{SrH}}_{\mathbf{2}}$

    Strontium hydroxide is $\mathbf{Sr}{\left(\mathrm{OH}\right)}_{\mathbf{2}}$

d. Magnesium oxide is $\mathbf{MgO}$

    Manganese(II) oxide is $\mathbf{MnO}$

Step 1: Formula for Lead(II) oxide and lead(IV) oxide

They differ in the number of oxygen because the charge of the lead in each compound is also different.

Lead (II) oxide is  $\mathbf{PbO}$

Lead(IV) oxide is  ${\mathbf{PbO}}_{\mathbf{2}}$

Step 2: Formula for lithium nitride, lithium nitrite, and lithium nitrate

They differ in the anion. 

Nitride is ${\mathbf{N}}^{\mathbf{3}\mathbf{-}}$

Nitrite is ${\mathbf{NO}}_{\mathbf{2}}^{\mathbf{-}}$${\mathbf{NO}}_{\mathbf{2}}^{\mathbf{-}}$

Nitrate is ${\mathbf{NO}}_{\mathbf{3}}^{\mathbf{-}}$

Lithium nitride is  ${\mathbf{Li}}_{\mathbf{3}}\mathbf{N}$

Lithium nitrite is  ${\mathbf{LiNO}}_{\mathbf{2}}$

Lithium nitrate is  ${\mathbf{LiNO}}_3$

Step 3: Formula for strontium hydride and strontium hydroxide

They also differ in anion         

Hydride is ${\mathbf{H}}^{\mathbf{-}}$

Hydroxide is ${\mathbf{OH}}^{\mathbf{-}}$

Strontium hydride is ${\mathbf{SrH}}_{\mathbf{2}}$

Strontium hydroxide is $\mathbf{Sr}{\left(\mathrm{OH}\right)}_{\mathbf{2}}$

Step 4: Formula for magnesium oxide and manganese(II) oxide.

They differ in cation.

Magnesium oxide is $\mathbf{MgO}$

Manganese(II) oxide is $\mathbf{MnO}$