Question

please answer to my this question tommarow my exam .​

Answer 1

magnesium ion is electrically charged because magnesium loses electrons to form Mg2+ ion which is posatively charged

for average atomic mass

just add both the masses divided by no of given isotopes which in this case is two

hence avg atomic mass of Br=79+81/2=80 amu

Answer 2

Atoms are electrically neutral because they have equal numbers of protons (positively charged) and electrons (negatively charged). If an atom gains or loses one or more electrons, it becomes an ion. If it gains one or more electrons, it now carries a net negative charge, and is thus aniionic..

Hope it helps