Depending on the bottle, it may still be good. It is highly likely that some of the fruit has faded. White wines ordinarily have less staying power than reds as a general rule but there are always exceptions.
Increasing your odds of your chardonnay being good, is the age of the wine. If is is young, it has a better chance than if it is from an older vintage. I find the vacuum stoppers to work excellent when used correctly. Vacu-Vin is the best product, but many people will over pumpm hence succking the oxygen out of the wine and articially aging it. I have stored wines for a week or more with great results simply bu using the vacu-vin. The instructions say about 5 pumps, however the amount of wine remaining in a bottle will vary. I satrt with 5 pumps and as soon as I feel the slightest change in resistance, I know it is adequate! Good luck and I hopoe this helps!