To solve this, we can use two equations.
t1/2 = ln 2 / λ = 0.693 / λ
where, t1/2 is half-life and λ is the decay constant.
t1/2 = 10 min = 0.693 / λ
Hence, λ = 0.693 / 10 min - (1)
Nt = Nο e∧(-λt)
Nt = amount of atoms at t =t time
Nο= initial amount of atoms
t = time taken
by rearranging the equation,
Nt/Nο = e∧(-λt) - (2)
From (1) and (2),
Nt/Nο = e∧(-(0.693 / 10 min) x 20 min)
Nt/Nο = 0.2500
Percentage of remaining nuclei = (nuclei at t time / initial nuclei) x 100%
= (Nt/Nο ) x 100%
= 0.2500 x 100%
= 25.00%
Hence, Percentage of remaining nuclei is 25.00%
Answer:
decreased by a factor of 10
Explanation:
pH is defined in such a way that;
pH= −log10(H)
Where H represents the concentration of Hydronium or Hydrogen ions
Given that pH is changed from 1 to 2,
By rearranging the above formula , we get 10−pH = H
- if pH=1,H=10−1=0.1M
- if pH=2,H=10−2=0.01M
Therefore, 0.1/0.01 = 10 and 0.1 > 0.01
Hence, the concentration of hydronium ions in the solution is decreased by a factor of 10
Answer:
The concentration of H⁺ in a 2.5 M HCl solution is 2.5 M
Explanation:
As HCl is a strong acid and hence a strong electrolyte, it will dissociate as
HCl ⟶ H⁺ + Cl⁻
So, The concentration of H⁺ will be 2.5 M (same as HCl)
Thus, The concentration of H⁺ in a 2.5 M HCl solution is 2.5 M
<u>-TheUnknownScientist</u><u> 72</u>
The puppies have different colored noses because of reccesive and dominant genotypes.
Genotypes are represented by letters, capital being dominant and lowercase being recessive.
For example, lets say t = pink nose and T = black nose.
If the parents have black noses, then they will pass on T genotypes.
But, they also have hidden pink nose genotypes.
These hidden genotypes are passed on to the puppies, one of the puppies gets more black nose genotypes.
If a puppy gets tt, they will have a pink nose.
If they get TT, they will have a black nose
If they get Tt, they will also have a black nose.
Because the black nose is dominant, its more likley for the puppies to end up with a black nose.