For each event, indicate how the concentration of each species in the chemical equation will then change to reach equilibrium. An up arrow indicates an increase in concentration, a down arrow indicates a decrease in concentration, and leaving it blank means there is no change in the concentration. 2 CO ( g ) + O 2 ( g ) − ⇀ ↽ − 2 CO 2 ( g ) increasing the concentration of CO increasing the concentration of CO 2 decreasing the volume of the system

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 !