Two identical iron spheres have equal positive charges and the force between them when they are 1 m apart is 1 N.What percentage of the electrons has been removed from each sphere if each sphere has 1 mole (6 x 10²³)of iron atoms? (k_e = 8.99 x 10⁹N*m²/C²,the atomic number of iron is 26,and the electron charge is -1.6 x 10^-19 C)

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The force between the spheres is given by Coulomb's law:$$F = k\frac{q_1q_2}{r^2}$$where k is Coulomb's constant, q1 and q2 are the charges on the spheres, and r is the distance between them.We are given that F = 1 N, r = 1 m, and k = 8.99 x 10^9 N F1F1F1S1F1F1F10m²/C².Substituting these values into Coulomb's law, we get:$$1 N = 8.99 x 10^9 N F1F1F1S1F1F1F10m²/C² \frac{q_1q_2}{(1 m)^2}$$$$q_1q_2 = 1.11 x 10^{-10} C^2$$Since the spheres have equal charges, we can write:$$q_1 = q_2 = \sqrt{1.11 x 10^{-10} C^2} = 1.05 x 10^{-5} C$$The number of electrons removed from each sphere is:$$n = \frac{q}{e} = \frac{1.05 x 10^{-5} C}{-1.6 x 10^{-19} C} = 6.56 x 10^{13}$$The percentage of electrons removed from each sphere is:$$\% = \frac{n}{N} imes 100\% = \frac{6.56 x 10^{13}}{6 x 10^{23}} imes 100\% = 4 x 10^{-10} \%$$Therefore, the correct answer is D.

Two Identical Iron Spheres Have Equal Positive Charges and the Force