Question

Question #dbb08

Answer 1

`F=(Q_1Q_2)/(r^2)`

Explanation:

Coulomb had defined the electrostatic force by:

`F=(Q_1Q_2)/(r^2)`

where, `Q_1 and Q_2` are the charges of the oppositely charged ions and `r` is the distance between the two nuclei.

For example, when comparing the electrostatic forces in two different ionic compounds we consider the following:

`NaCl` and `MgCl_2`:

We look at the difference in charges:

For `NaCl`, the product `Q_1Q_2=(+1)xx(-1)=-1`

For `MgCl_2`, the product `Q_1Q_2=(+2)xx(-1)=-2`

Which means that `F_(MgCl_2)>F_(NaCl)`.

`NaCl` and `CsCl`:

We look at the difference of `r`.

Since `Cs^+` is greater in size than `Na^+` therefore, `r_(CsCl)>r_(NaCl)` and thus `F_(NaCl)>F_(CsCl)`.