JAMB - Chemistry (2018 - No. 16)
Which of the following statements is correct about the periodic table?
Elements in the same period have the same number of valence electrons
The valence electrons of the elements in the same period increase progressively across the period
Elements in the same group have the same number of electron shells
The non-metallic Properties of the elements tend to decrease across each period
Vysvetlenie
The valence electrons refer to the number of electrons in the outer shell. Across a period (horizontal row), the valence electron increases.