Answer:
12.50g
Explanation:
T½ = 2.5years
No = 100g
N = ?
Time (T) = 7.5 years
To solve this question, we'll have to find the disintegration constant λ first
T½ = In2 / λ
T½ = 0.693 / λ
λ = 0.693 / 2.5
λ = 0.2772
In(N/No) = -λt
N = No* e^-λt
N = 100 * e^-(0.2772*7.5)
N = 100*e^-2.079
N = 100 * 0.125
N = 12.50g
The sample remaining after 7.5 years is 12.50g
Answer:
Name the element: Beryllium
Number of shells: 4
Valence electrons: 2
Explanation:
Answer:
migratory distribution
Explanation: The pattern of migratory distribution of species may require collaboration between different countries for effective preservation. This is because species migration can make them enter different territories, which will need to provide an effective level of preservation for species survival
Answer:
a mixture
Explanation:
in a mixture the substances havent chemically combined so it is easy to just separate them through physical means
