JAMB - Chemistry (2001 - No. 7)
Four elements W, X, Y and Z have atomic number 2,6,16 and 20 respectively. Which of these elements is a metal?
X
W
Z
Y
Explicació
Element Z has electronic configuration of 2, 8, 8, 2. This implies it's in group 2 (Alkaline earth metals). Actually, the element is most likely to be Calcium with an atomic number of 20. The correct answer is option C