Hello!
The half-life is the time of half-disintegration, it is the time in which half of the atoms of an isotope disintegrate.
We have the following data:
mo (initial mass) = 20 g
m (final mass after time T) = 5 g
x (number of periods elapsed) = ?
P (Half-life) = ? (in minutes)
T (Elapsed time for sample reduction) = 8 minutes
Let's find the number of periods elapsed (x), let us see:
![m = \dfrac{m_o}{2^x}](https://tex.z-dn.net/?f=%20m%20%3D%20%20%5Cdfrac%7Bm_o%7D%7B2%5Ex%7D%20)
![5 = \dfrac{20}{2^x}](https://tex.z-dn.net/?f=%205%20%3D%20%20%5Cdfrac%7B20%7D%7B2%5Ex%7D%20)
![2^x = \dfrac{20}{5}](https://tex.z-dn.net/?f=%202%5Ex%20%3D%20%5Cdfrac%7B20%7D%7B5%7D%20%20)
![2^x = 4](https://tex.z-dn.net/?f=%202%5Ex%20%3D%204%20)
![2^x = 2^2](https://tex.z-dn.net/?f=%202%5Ex%20%3D%202%5E2%20)
![\boxed{x = 2}](https://tex.z-dn.net/?f=%20%5Cboxed%7Bx%20%3D%202%7D%20)
Now, let's find the half-life (P) of the radioactive sample, let's see:
![T = x*P](https://tex.z-dn.net/?f=%20T%20%3D%20x%2AP%20)
![8 = 2*P](https://tex.z-dn.net/?f=%208%20%3D%202%2AP%20)
![2\:P = 8](https://tex.z-dn.net/?f=%202%5C%3AP%20%3D%208%20)
![P = \dfrac{8}{2}](https://tex.z-dn.net/?f=%20P%20%3D%20%5Cdfrac%7B8%7D%7B2%7D%20%20)
![\boxed{\boxed{P = 4\:minutes}}\Longleftarrow(Half-Life)\end{array}}\qquad\checkmark](https://tex.z-dn.net/?f=%20%5Cboxed%7B%5Cboxed%7BP%20%3D%204%5C%3Aminutes%7D%7D%5CLongleftarrow%28Half-Life%29%5Cend%7Barray%7D%7D%5Cqquad%5Ccheckmark%20)
I Hope this helps, greetings ... DexteR! =)
Answer:
For 6.50 mol NaOH - 1.44M.
For 6.50 g NaOH - C. 0.0361 M
Explanation:
For 6.50 mol NaOH.
Molarity = moles solute/L solution = 6.5 mol/4.5 L solution = 1.44 mol/L=1.44M
There is no such answer in given choices.
For 6.50 g NaOH
M(NaOH) = 23 + 16 + 1 = 40 g/mol
Molarity = 6.5g* 1 mol/40g *1/4.5L = 0.0361 mol/L = 0.0361 M
There is such answer. It is C.
B - brown eyes
b - blue eyes
If we were to fill out a punette square each of his sex cells would contain at least one brown eyed gene.