The abstract names differ from concrete names because they refer to immaterial entities, which can neither be touched nor felt nor tasted nor seen nor smelled.
They are objects existing only in our mind, as concepts purely separate from the substance of things, feelings, ideas, emotions.
These nouns mostly end in -tà, -anza, -enza, -ezza, -ione, -izia, -igia, -ura.
Some of them derive from verbs and express the action or the effect of that same action (beauty - bellezza, injustice - ingiustizia , fear - paura, etc.).
I hope it is helpful to you!