If an atom of magnesium loses a proton, what happens to its atomic number and identity?
The atomic number decreases by one and it becomes a new element
The atomic number of an element is the number of protons in the nucleus of its atom. It is this number of protons that fixes the identity of the element, so every atom with 12 protons is magnesium.
Magnesium has atomic number 12. If an atom loses one proton, it is left with 11 protons, so its atomic number decreases by one to 11. An atom with 11 protons is sodium, so the atom has become a new element.
The atomic number cannot increase when a proton is lost. Becoming an ion involves gaining or losing electrons, not protons, and isotopes are atoms of the same element that differ in the number of neutrons, not protons.
Hence, The atomic number decreases by one and it becomes a new element.
Similar Questions
Consider the following statements regarding Thomson's model of an atom.
Statement I: The atom is a sphere of positive charge with electrons scattered inside it.
Statement II: Thomson's model could explain the presence of the nucleus in an atom.
Which of the following is TRUE?
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Which of the following electron transition in hydrogen atom will require largest amount of energy?
A species having 8 electrons in the third shell is very reactive while the other species having 8 electrons in the third shell is very inactive they are :
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