Answer:
140.32mL per hour
Step-by-step explanation:
Rate of leakage of nitrogen ballon = 75 mL/h
Rate of leakage of helium ballon = x
Molar mass of nitrogen= Mn = 14
Molar mass of helium = Mh = 4
Effusion formula
Rate of effusion of helium/ Rate of effusion of nitrogen= √(Molar mass of nitrogen/Molar mass of helium)
Rate of effusion of helium = 75mL/h * √(14/4)
= 140.32mL/h