Oxygen is in group 16 of the PTOE, so it has 6 valence electrons. In order to have a full outer shell it would need 2 more electrons. (second shell can hold a max of 8 electrons)
Precision relates to how close the answers are to each other, so I’d think it would be D because of the limited range between data points.
Mass number = protons + neutrons = 34+46 =80
the element with an atomic number of 34 and mass number of 80 is selenium
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:
That we know about yes, but physicians still say there are more things out there. (we do not know about these yet tho)
Explanation:
