I would just add, while what Awaclus said can be relevant sometimes, do not change your opening buys just because of that, if the other card youīre going for costs 4 you buy it on the turn you have 4 on hand, be that turn 1 or 2. (In a similar vein to what he said, though, itīs frequently a good move to not play all your treasures if you donīt need all your money, if you buy chapel, for example, on turn 1 showing 3 coppers, your opponent will know you did not open 2/5 and can plan with that knowledge, also on endgame showing a lot more money than necessary, might be a hint to your opponent that the rest of your shuffle might be susceptible to duding, etc...)
Adding to the list of cases of Chapel openings that matter between turn 1 or 2, I would say itīs missing possibly the one that possibly matters the most. Turn 1 Summon on Chapel is quite possibly one of the best openings out there and itīs not nearly as good on turn 2, ...