Tutor profile: Pranita D.

How do you calculate the slope of a line?

Rise over run. Rise refers to the difference in height between two points on the line, and run refers to the difference in linear distance between the same two points.

Explain the trend in electronegativity across a period.

As you move across a period, the number of protons increases, but the number of shells remains the same. Because the number of shells remains constant, the outermost electrons experience a similar amount of shielding from the inner shells. This means that moving across, the outermost electrons experience a stronger attraction to the nucleus because the positive charge in the nucleus is increasing but the shielding remains around the same. Therefore, electronegativity increases across a period. The increasing positive charge attracts the bonded electrons more strongly.

What is electronegativity?

Electronegativity is the tendency of an atom in a bond to attract electrons towards itself. For example, in an HCl molecule, Cl is more electronegative than H, and therefore, the pair of electrons shared in the covalent bond is attracted more towards the Cl end.