Radioactive decay is expressed by the following formula:
N₀ is the initial number of undecayed atoms.
Nt is the number of undecayed atoms remaining after time t
λ is the decay constant.
The relationship between λ and the half life time t1/2 is:
λ =
= 0.693 / 5.27 = 0.1315
Taking natural logs for both sides of the decay expression:
ln Nt = ln N₀ - λ t
ln Nt = ln 199 - (0.1315 x 20)
= 5.293 - 2.63 = 2.66
From which:
Nt = 14.29 g
The answer is 12.5 grams of Tc-99.
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You have 3 six-hour cycles in 18h. So it's
First cycle is half of 100 = 50
Second cycle is half of 50 = 25
Third cycle is half of 25 which is 12.5
Answer:
The final vapor pressure is 687.24mmHg
Explanation:
The clausius-clapeyron equation below will be used to solve this problem:
Where;
ΔH is heat of vaporization = 450 kJ/mol = 450000J/mol
initial vapor pressure P₁ = 400mmHg
initial temperature T₁ = 3030K
Final temperature T₂ = 3070K
R is ideal gas constant = 8.314 J/molK
final vapor pressure P₂ = ?
P₂/400 = 1.7181
P₂ = (400*1.7181)mmHg
P₂ = 687.24mmHg
The final vapor pressure is 687.24mmHg
The freezing point of a solution will increase and the vapor pressure will increase with decreasing <span>molality of a nonvolatile solute. The correct option among all the options that are given in the question is the second option or option "B". I hope the answer has come to your help. </span>
Toe? Do you mean which toe like feet or a different toe
Explanation: