Which set of elements is arranged in order of increasing electronegativity?

• A. Na, Mg, Al, Si
• B. Mg, Na, Si, Al
• C. Si, Al, Mg, Na
• D. Al, Na, Mg, Si

Answer: (A)

Verified step by step guidance

1. Recall that electronegativity is the tendency of an atom to attract electrons in a chemical bond, and it generally increases across a period (left to right) in the periodic table and decreases down a group (top to bottom).
2. Identify the elements given: Na (Sodium), Mg (Magnesium), Al (Aluminum), and Si (Silicon), which are all in the same period (Period 3) of the periodic table.
3. Since these elements are in the same period, their electronegativity increases as you move from left to right: Na < Mg < Al < Si.
4. Compare each answer choice to this order to find the set that correctly lists the elements in order of increasing electronegativity.
5. Select the answer choice that matches the sequence Na, Mg, Al, Si, as this reflects the correct increasing order of electronegativity for these elements.