Question

for each list, place elements in order of least to greatest electronegativity: 1) cl chlorine na sodium si silicon 2) in indium ga gallium b boron 3) na sodium o oxygen si silicon

Explanation:

Step1: Recall electronegativity trends

Electronegativity increases across a period and decreases down a group in the periodic - table.

Step2: Analyze the first set (Cl, Na, Si)

Na is a metal in Group 1, Si is a metalloid in Group 14, and Cl is a non - metal in Group 17 of the same period. So, the order is Na < Si < Cl.

Step3: Analyze the second set (In, Ga, B)

B is in Period 2, Ga is in Period 4, and In is in Period 5 of Group 13. So, the order is In < Ga < B.

Step4: Analyze the third set (Na, O, Si)

Na is a metal in Group 1, Si is a metalloid in Group 14, and O is a non - metal in Group 16. Na is in Period 3, O is in Period 2. So, the order is Na < Si < O.

Answer:

1. Na, Si, Cl
2. In, Ga, B
3. Na, Si, O