Mango
Prune
Apple
Guava
Grape
I would have thought you meant sorbet, apart from the 5 letters
applegrapelemonmangomelonpeachprune
Juice
The likely word is "juice."
Punch
Juice
Juice
Mango juice :)
I would have thought you meant sorbet, apart from the 5 letters
cider
i really am not sure, but i'll just throw a wild guess out there. Lemon? it is a juice that is always an acid, and has 5 letters.
applegrapelemonmangomelonpeachprune
Juice
peach
Apple, lemon, mango, prune
If one fourth of the 5 gallons of fruit punch was cranberry juice, you can calculate the amount of cranberry juice by multiplying 5 gallons by 1/4. This equals 5 x 1/4 = 1.25 gallons. Therefore, Bill used 1.25 gallons of cranberry juice in the fruit punch.
A lemon is yellow, egg-shaped, with 5 letters.