) The cooling or warming of air that occurs because air is allowed to expand or is compressed, not because it is added or subtracted is called .

Adiabatic temperature changes.

Explanation:

Temperature changes related to changes of pressure without external gain or loss of heat. If no heat is added or lost to the surroundings, then when an air parcel rises and expands, its temperature drops. Conversely, when the parcel is compressed, its temperature rises. So the term adiabatic, implies a change in temperature of the air parcel without gain or loss of heat from outside the air parcel.

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !