Question

Incorrect statement(s) for the second period's elements of the modern periodic table are

• A. All the elements produce cations after the loss of electrons.
• B. All the second period's elements have 2 energy levels
• C. Number of neutrons is less than the number of protons in atoms.
• D. All the second period's elements have same chemical properties

Answer 1

Answer: (A), (C), (D)

All the second period's elements have same chemical properties

From the given statements,
(A) Elements in period 2 that form cations are only metals i.e, Li,Be. Other elements in the second period are metalloids and nonmetals which have the tendency to gain electrons and form anions. So not all elements in the $2^{nd}$ period lose electrons to form cations.
(B) Atoms belonging to a particular period have the same number of energy levels as that period number. So, $1^{st}$ period has 1 energy level, and the $2^{nd}$ period has 2 energy levels.
(C) Never in $2^{nd}$ period's elements the number of neutrons are less than the number of protons in atoms, they are either greater than or equal to the number of protons.
(D) As the numbers of electrons are different for different elements in the $2^{nd}$ period, their chemical properties also differ.