What increases in equal steps of one from left to right in the periodic table for the elements lithium to neon?

The one that increases in equal steps of one from left to right in the periodic table for the element lithium to neon is the proton number. You can see this yourself using the periodic table. Looking in the periodic table for the elements lithium to neon you can see that the proton number is increasing in equal steps. The answer is the proton number.