The mass of substance left after 7 days is 13.09 g
The mass of substance left, N is given by
N = N₀exp(-λt) where λ = decay constant and N₀ = initial mass of substance present = 24 g and t = time
Also, λ = 0.693/t' where t' = half-life of iodine = 8 days
So, λ = 0.693/t'
λ = 0.693/8
λ = 0.086625/day
Since the mass of substance left is N = N₀exp(-λt) and we require the mass of substance after t = 7 days,
N = N₀exp(-λt)
N = 24 gexp(-0.086625/day × 7 days)
N = 24 gexp(-0.606375)
N = 24 g × 0.5453
N = 13.09 g
So, the mass of substance left after 7 days is 13.09 g
Learn more about radioactive decay here:
brainly.com/question/23705307
Answer: The formula to calculate the radius of a sphere if we know the volume is: Cubic root [3V/(4∏)].
Solution:
The formula for the volume (V) of a sphere is:
V=(4∏/3) r^3
Solving for r: Multiplying both sides of the equation by 3/(4∏):
3/(4∏) V = 3/(4∏) [(4∏/3) r^3]
3V/(4∏) = r^3
Cubic root both sides of the equation (raising to the power 1/3):
Cubic root [3V/(4∏)] =Cubic root (r^3)
Cubic root [3V/(4∏)] = r
r = Cubic root [3V/(4∏)]
Answer:
Step-by-step explanation: