Understand Specific Charge for AS Level Physics

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Specific charge refers to the charge-to-mass ratio of an ion, and in the case of the magnesium ion mentioned, it has a charge of +3.2 x 10^-19 Coulombs due to the loss of electrons. The charge of a proton is indeed 1.60 x 10^-19 Coulombs, but the total charge of the ion is not simply the number of protons multiplied by the charge of a proton because the ion is positively charged, indicating it has lost electrons. The confusion arises from not accounting for the electrons that balance the charge in a neutral atom. The relative charge of the magnesium ion is +2, confirming it has lost two electrons. Understanding the role of electrons is crucial in grasping the concept of specific charge in ions.
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Hello, i have recently started doing AS level physics and i don't understand specific charge.
My textbook stated ' An ion of Magnesium isotope (24 nucleon number, 12 proton number) has a charge of +3.2 x 10(to the power of negative 19) Coulombs.
The charge of a proton is : 1.60 x 10(to the power of negative 19)
As the ion has 12 protons in the nucleus, why isn't the charge (1.60 X 10^-19) x 12?
If anybody could explain it would be much appreciated:)
 
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Hint: if it isn't an ion, the net charge would be zero. You are forgetting the electrons surrounding the nucleus.

Zz.
 
Ohh, so is the relative charge of the ion +2?
 
It may be shown from the equations of electromagnetism, by James Clerk Maxwell in the 1860’s, that the speed of light in the vacuum of free space is related to electric permittivity (ϵ) and magnetic permeability (μ) by the equation: c=1/√( μ ϵ ) . This value is a constant for the vacuum of free space and is independent of the motion of the observer. It was this fact, in part, that led Albert Einstein to Special Relativity.
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