Question

Which of these pairs of elements have the same number of valence electrons?

Answer 1

Carbon (C) and lead (Pb) 4e⁻

C [He]2s²2p²

Pb [Xe]6s²4f¹⁴5d¹⁰6p²

Answer 2

Answer: The correct answer is Carbon (C) and Lead (Pb)

Explanation:

Valence electrons is defined as the electrons which are present in the outermost shell of the element.

For the given options:

Option 1: Oxygen (O) and Bromine (Br)

Electronic configuration of Oxygen : $1s^22s^22p^4$

Electronic configuration of Bromine : $[Ar]4s^23d^{10}4p^5$

Oxygen has 6 valence electrons and bromine has 7 valence electrons.

Option 2: Selenium (Se) and Bromine (Br)

Electronic configuration of Selenium : $[Ar]4s^23d^{10}4p^4$

Electronic configuration of Bromine : $[Ar]4s^23d^{10}4p^5$

Selenium has 6 valence electrons and bromine has 7 valence electrons.

Option 3: Carbon (C) and Lead (Pb)

Electronic configuration of Carbon : $1s^22s^22p^2$

Electronic configuration of Lead : $[Xe]6s^25d^{10}6p^2$

Carbon has 4 valence electrons and lead also has 4 valence electrons.

Option 4: Oxygen (O) and carbon (C)

Electronic configuration of Oxygen : $1s^22s^22p^4$

Electronic configuration of Carbon : $1s^22s^22p^2$

Oxygen has 6 valence electrons and carbon has 4 valence electrons.

Option 5: Sodium (Na) and Magnesium (Mg)

Electronic configuration of Sodium : $1s^22s^22p^63s^1$

Electronic configuration of Carbon : $1s^22s^22p^63s^2$

Sodium has 1 valence electrons and magnesium has 2 valence electrons.

From the above information, the correct answer is Carbon (C) and Lead (Pb)