Answer:
a)- Se, S, O
b)- Na, P, Cl
c)- S, Cl, F
d)- P, N, O
Step-by-step explanation:
We can solve this problem by looking at the Periodic Table. In a group, electronegativity increases from bottom to top; whereas in periods it increases from left to right.
Thus, we order the elements from lower to higher electronegativity as follows:
a. Se, O, S ⇒ order: Se, S, O
Because they are all in the same group. Se is near the bottom, followed by S and O is at the top.
b. P, Na, Cl ⇒ order: Na, P, Cl
They are in the same period. Na is at the left, followed by P and Cl is nearest the right.
c. Cl, S, F ⇒ order: S, Cl, F
P and Cl are in the same period, and P is at the left, so it has the lowest electronegativity. F is in the same group of Cl, but at the top. F has the highest electronegativity.
d. O, P, N ⇒ order: P, N, O
N and P are in the same group, but P is at the bottom so it has the lower electronegativity. N and O are in the same period, but O is at the right, so it is the most electronegative.