Aliquid in a stoppered flask is allowed to stand at constant temperature until the liquid level in the flask remains constant. which condition then exists in the flask

Equilibrium

Explanation:

The condition that exists in the flask is called equilibrium.

An equilibrium is a state when the rate of forward reaction equals the rate of backward reaction. A liquid contained in a stoppered flask exhibits evaporation and condensation. The former involves a change in phase from liquid to gas while the latter involved change from gas to liquid. This process continues until an equilibrium is reached when the rate of evaporation equals the rate of condensation. At this point the level of water in the flask becomes constant.

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 !