A square shaped aluminium coin weighs 0.75 ~g and its diagonal measures 14 ~mm . It has equal amounts of positive and negative charges. Suppose those equal charges were concentrated in two charges (+Q and -Q) that are separated by a distance equal to the side of the coin, the dipole moment of the dipole is

Step-by-step solution

The mass of the aluminium coin is m = 0.75 g . The molar mass of aluminium is M = 27 g/mol . The number of moles of aluminium is n = m M = 0.75 27 = 1 36 mol . The number of atoms in the coin is N = n N_A = 1 36 6.022 10²³ 1.67 10²² atoms. Each aluminium atom has an atomic number Z = 13 . Thus, the total number of protons (or electrons) in the coin is N_ total = N Z = 1.67 10²² 13 2.17 10²³ . The total charge Q is N_ total e , where e = 1.6 imes 10⁻¹⁹ C . So, Q = 2.17 10²³ 1.6 10⁻¹⁹ 3.47 10^4 C . The diagonal of th