So half life is the time taken for a sample to decay to half its original mass, its a constant and applies to any original mass, it could be 5g or 1kg, it will take the same amount of time for the original mass to half. In this case the half life is 3 days.
After 3 days the sample will be at half its original mass, now 50g.
Now we can treat the 50g as if its a new sample. After another 3 days (6 days in total) there will be half of 50g left, = 25g.
Answer:
The gas obeys Boyle’s law and the value of
both are equal to 40.0 atm L.
Explanation:
Initial volume of the gas = 
Initial pressure of the gas = 
Final volume of the gas = 
Final pressure of the gas = 
This law states that pressure is inversely proportional to the volume of the gas at constant temperature.

The equation given by this law is:








The gas in the cylinder is obeying Boyle's law.
The gas obeys Boyle’s law and the value of
both are equal to 40.0 atm L.
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