Enthalpy is said to be additive

[Andrea_Torres]

What does it mean for something to be additive?

[Julie Park 1G]

It's saying that since enthalpy is a state property (not dependent on the path taken to obtain that state), enthalpies can be added (and subtracted).
For example, Hproducts - Hreactants = Change in H

[WesleyWu_1C]

One of the examples that Dr. Lavelle gave for another state property is altitude. For altitude, the path doesn't matter. What matters is where the hiker ends up.

[Jasmine 2C]

it basically means the delta H values can be added together (even if it's a negative number, which will just make the addition into a subtraction)

[kevinolvera1j]

Because Enthalpy is a state function, only the state matters. In other words, what matters is the state, not the way that those states were obtained or the path that led them there. This is what allows enthalpy to be additive.

[Chris Charton 1B]

This is because Enthalpy is a state property. Only the initial and final values are relevant, the path taken to get to the final value does not matter.

[gabbymaraziti]

Enthalpy is additive because it is a state function, meaning it can be added or subtracted.

[Eesha Chattopadhyay 2K]

being additive means that different enthalpies of different reactions can be added. this is true because enthalpy is a state function.

[RasikaObla_4I]

Because enthalpies of different reactions can be added together, it is said to be additive.

[Nare Nazaryan 1F]

It just means that, since enthalpy is a state property, different enthalpies can be added together.

[805422680]

enthalpies of different reactions can be added together to get the total enthalpy of the system in its change from reactants to products