Group 2 elements are the alkaline earth metals
The question is incomplete, the complete question is;
Atom Number of protons Number of electrons Number of neutrons
1 39 39 52
2 40 40 50
3 39 39 54
4 40 40 51
Based on the information that is given, which atom in the table has the highest mass?
a. 1
b. 2
c. 3
d. 4
Answer:
c
Explanation:
The relative atomic mass is given as; number of protons + number of neutrons. If we take the relative atomic mass of each of the options;
1) 39 +52 = 91
2) 40+50 = 90
3) 39 + 54 = 93
4) 40 + 51 = 91
Thus 3 has the highest mass as seen above, hence the answer given.