where a = -9.81 m/(s^2), v = the original velocity, x is the original x position, and t is time.
Assuming x = 0 m, v = 0 m/s, we have
X = (1/2)(-9.81 m/(s^2))(10 s)^2 = -490.5 m
Without air resistance, the ball would've fallen 490.5 meters. However I'm sure that it would've reached terminal velocity before then :)