Question

Which of the following sets belongs to the same period:

• A. $Li,Na,K$
• B. $Li,Mg,Ca$
• C. $Ni,Cu,Zn$
• D. $F,Cl,Br$

Answer 1

The correct option is C $Ni,Cu,Zn$

A period in the periodic table is a horizontal row. All elements in a row have the same number of electron shells.

Each next element in a period has one more proton and is less metallic than its predecessor.

$Ni,Cu,Zn$ belongs to the $3rd$ period in the periodic table .