  Question

# The electronegativity of the followingelements increases in the order C, N, Si, P N, Si, C, P Si, P, C, N P, Si, N, C

Solution

## The correct option is C Si, P, C, N The elements in the question are: C → 1s2 2s2 2p2                          (2nd period) N → 1s22s22p3 (2nd period) Si → 1s22s22p63s23p2     (3rd period) P → 1s22s22p63s23p3      (3rd period) We know that, In a period moving from left to right, the electronegativity increases due to the increase in effective nuclear charge. Ina group moving from top to bottom, the electronegativitiy decreases because atomic radius increases. because Atomic Radius: As the atomic radius of the element increases the electronegativity value decreases. Electronegativity α 1atomicradius and Effective Nuclear Charge: The electronegativity value increases as the effective nuclear charge on the atomic nucleus increases. Electronegativity ∝Effective nuclear charge (Zeff) Now, if we look at the atomic radius of these elements. Si > P > C > N (Atomic radius) Therefore, N > C > P > Si (Electronegativity) ⇒ I hope, now you are clear with the idea.  Suggest corrections   