Question

Which of these would BEST describe the structural difference between magnesium and aluminum?

Answer 1

The right answer is B) Magnesium has one less proton than aluminum.  

Magnesium is the chemical element of atomic number 12, Mg symbol.

Magnesium 24 is composed of 12 protons and 12 neutrons. Mg 25 and Mg 26 respectively have 13 and 14 neutrons.

Aluminum is the chemical element of atomic number 13, symbol Al. It belongs to group 13 of the periodic table and to the family of poor metals.

Aluminum 27 is composed of 13 protons and 14 neutrons.

Answer 2

The only true answer here is B. if you have a periodic table, you can see that Magnesium atomic number is 12 while Aluminium's is 13. this means Al has 1 more proton and weights more than magnesium since proton and neutrons contribute to the weights of the atoms.