You did not provide possible answers, but one possible might be that the current atomic theory is so sound and plausible that there should not be anything that could change it in the near future.
We can use two equations for this problem.<span>
t1/2 = ln
2 / λ = 0.693 / λ
Where t1/2 is the half-life of the element and λ is
decay constant.
20 days = 0.693 / λ
λ = 0.693 / 20 days
(1)
Nt = Nο eΛ(-λt) (2)
Where Nt is atoms at t time, No is the initial amount of substance, λ is decay constant and t is the time
taken.
t = 40 days</span>
<span>No = 200 g
From (1) and (2),
Nt = 200 g eΛ(-(0.693 / 20 days) 40 days)
<span>Nt = 50.01 g</span></span><span>
</span>Hence, 50.01 grams of isotope will remain after 40 days.
<span>
</span>
Answer:
I think acetone has more because water is just H20
First, in order to calculate the specific heat capacity of the metal in help in identifying it, we must find the heat absorbed by the calorimeter using:
Energy = mass * specific heat capacity * change in temperature
Q = 250 * 1.035 * (11.08 - 10)
Q = 279.45 cal/g
Next, we use the same formula for the metal as the heat absorbed by the calorimeter is equal to the heal released by the metal.
-279.45 = 50 * c * (11.08 - 45) [minus sign added as energy released]
c = 0.165
The specific heat capacity of the metal is 0.165 cal/gC
A B and C are all chemical changes. paper tearing is not.
