The mass of one atom is almost all as result of the protons and also neutrons in the nucleus. The atom mass number is the variety of protons included to the number of neutrons and also is provided the price A. Because that this atom the lithium, A equates to 6.
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The variety of protons in the cell nucleus of an atom is referred to as the atomic number. It has the price Z. The atomic variety of lithium is 3.
We can present the atomic mass number and the atom number with the symbol because that the element.
A is the number of neutrons plus protons in the nucleus.However, we already know that there are 7 protons. Therefore, there need to be 8 neutron in the cell nucleus to add up to 15.
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