Question

how does electronegativity change across the period ?

1. label your x-axis as atomic number and the y-axis as the electronegativity.
2. go to table s. fill in the table below

element name	atomic number	electronegativity
beryllium
boron
fluorine

1. plot the data on your graph.

Explanation:

To answer how electronegativity changes across a period, we first fill the table with known data:

• Lithium (Li): Atomic Number = 3, Electronegativity (Pauling scale) ≈ 1.0
• Beryllium (Be): Atomic Number = 4, Electronegativity ≈ 1.57
• Boron (B): Atomic Number = 5, Electronegativity ≈ 2.04
• Fluorine (F): Atomic Number = 9, Electronegativity ≈ 3.98

After plotting (x: atomic number, y: electronegativity), we observe the trend: As atomic number increases across a period (from left to right), electronegativity generally increases. This is because as we move across a period, the number of protons in the nucleus increases (increasing nuclear charge) while the shielding effect from inner electrons remains relatively constant. The increased nuclear charge pulls the bonding electrons more strongly, leading to a higher electronegativity.

Answer:

Filled Table:

Element name	Atomic Number	Electronegativity
Beryllium	4	~1.57
Boron	5	~2.04
Fluorine	9	~3.98

Trend:

Electronegativity increases as the atomic number increases across a period (from left to right in the periodic table).