Answer:
Explanation:
An atom is composed of a nucleus and electrons orbiting around it,and the nucleus itself contains protons and neutrons (with the exception of protium, an isotope of hydrogen with only a proton in the nucleus) because each element contains a specific and unique number of protons, but the number of neutrons can vary,an element, therefore, can have several variants, called isotopes, which differ slightly in the composition of the nucleus,the number of electrons can also change in an atom, giving us positive or negative ions.
=Br-79 has 79 nucleons. 79 protons and neutrons. We know that bromine has 35 protons, and 35 electrons, so all we need to do is subtract. 79 nucleons - 35 protons = 44 neutrons,
Subtract the atomic number from the mass number,the result gives you the number of neutrons in the isotope,look to see if the isotope has a charge, denoted by a superscript number and a plus or minus sign next to it,subtract the charge from the atomic number if the charge is positive,the result is the number of electrons in the isotope,add the absolute value of the charge to the atomic number if the charge is negative,the result is the number of electrons in the isotope.
= 35 from 79 and you will get 44. 44 is the number of neutrons in the Br-79 isotope.
79-Br+, that means:
It’s still a Br (bromine) atom, so it doesn’t change the number of protons //because changing the number of protons, it won’t be bromine anymore//
So bromine atom has 35 protons
So, isotope means many forms of atoms with the same element, which are different from atomic mass (or more clearly, the number of neutrons) → 79 (this number is shown for the atomic mass) - 35 = 44 neutrons
It has 35 protons, 34 electrons and 44 neutrons. The way to figure this out is - the protons of an element never change. So when you say bromine, you look it up on the Periodic table and you see its atomic number (aka # of protons) is 35. It will always be 35 for bromine. Then you take the charge into account. In this case, the charge is +1. Since protons can’t change, electrons must. One more proton equals one less electron. So 34 electrons. The atomic weight of a number (79 in this case) is = # of protons + # of neutrons. So neutrons = 79 - 35 = 44.
Hope this helps!
