Ion interaction energies are determined by Coulomb's law: $$E = \left( 2.31 \times 10 ^ { - 19 } J \cdot n m \right) \left( \frac { Q _ { 1 } Q _ { 2 } } { d } \right)$$ Determine the energy of potassium chloride if the radius of the potassium ion is 133 pm and that of the chloride ion is 181 pm.

Question

Quizplus · Accepted Answer

The total distance between ions is the sum of their radii: 133 pm + 181 pm = 314 pm = 0.314 nm. Using Coulomb's law with charges Q1 = +1 and Q2 = -1, the energy is calculated as E = (2.31 x 10^-19 J·nm) * ((1 * -1) / 0.314 nm) = -7.36 x 10^-19 J.

Ion Interaction Energies Are Determined by Coulomb's Law E=(2.31×10−19J⋅nm)(Q1Q2d)E = \left( 2.31 \times 10 ^ { - 19 } J \cdot n m \right) \left( \frac { Q _ { 1 } Q _ { 2 } } { d } \right)E=(2.31×10−19J⋅nm)(dQ1​Q2​​)

Ion Interaction Energies Are Determined by Coulomb's Law $E = \left( 2.31 \times 10 ^ { - 19 } J \cdot n m \right) \left( \frac { Q _ { 1 } Q _ { 2 } } { d } \right)$