Answer:
43.7
Step-by-step explanation:
Volume of gas = 1.00L
Time = 12 hours
Decrease in 1 balloon = 0.200L
Decrease in second balloon = 0.0603L
R1 = rate at which helium diffuses= 0.20/12= 0.0166
R2 = rate at which heavier gas diffuses = 0.0693/12 = 0.00502
Using grahms law
R1²/R2² = m/4
= 0.0166²/0.00502² = m/4
= 10.935 = m/4
When we cross multiply
m is the molar mass of heavier gas = 43.73