What is the name of the molecule below

A) 2-pentene

Explanation:

We count from side where we encounter double bond closest so that's going to be from left to the 2nd carbon. Total carbons are 5.

Thus pent- for prefix of 5 carbons and -ene as suffix for double bond.

2- for locant of double bond.

Thus, 2-pentene

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 !