The general equation for radioactive decay is;
N = N₀e^(-λt)
x - decay constant (λ) - rate of decay
t- time
N - amount remaining after t days , since we are calculating the half life, amount of time it takes for the substance to to be half its original value, its N₀/2
N₀ - amount initially present
substituting the values
N₀/2 = N₀e^(-0.081t)
0.5 = e^(-0.081t)
ln (0.5) = -0.081t
-0.693 = -0.081t
t = 0.693 / 0.081
= 8.55
half life of substance is 8.55 days
<span>I’ve answered this
question before so if these are the choices to the question presented:
An oxygen atom double-bonded to a carbon atom, with a hydrogen atom
single-bonded to the same carbon atom. </span><span>
<span>A hydrogen atom covalently bonded to an oxygen atom, which is
covalently bonded to a carbon in the carbon chain. </span>
<span>A carbon atom single-bonded between two other carbon atoms,
with an oxygen atom double-bonded to the central carbon atom as well. </span>
<span>An oxygen atom single-bonded between two carbon atoms within
a carbon chain.
Then, the answer would be “a hydrogen atom covalently bonded to an oxygen atom,
which is covalently bonded to a carbon in the carbon chain.<span>”</span></span></span>
Molar mass of 13c = 13 grams
number of moles = mass / molar mass
therefore,
number of moles = 7 / 13
To know the number of atoms in 7/13 moles, we simply multiply the number of moles by Avogadro's number as follows:
number of atoms = (7/13) x 6.022 x 10^23 = 3.2426 x 10^23 atoms
A - its condensation and gas particles have a higher kinetic energy
At 40 degrees Celsius, approximately 78 grams of potassium bromide can be dissolved.
