It would take 147 hours for 320 g of the sample to decay to 2.5 grams from the information provided.
Radioactivity refers to the decay of a nucleus leading to the spontaneous emission of radiation. The half life of a radioactive nucleus refers to the time required for the nucleus to decay to half of its initial amount.
Looking at the table, we can see that the initial mass of radioactive material present is 186 grams, within 21 hours, the radioactive substance decayed to half of its initial mass (93 g). Hence, the half life is 21 hours.
Using the formula;
k = 0.693/t1/2
k = 0.693/21 hours = 0.033 hr-1
Using;
N=Noe^-kt
N = mass of radioactive sample at time t
No = mass of radioactive sample initially present
k = decay constant
t = time taken
Substituting values;
2.5/320= e^- 0.033 t
0.0078 = e^- 0.033 t
ln (0.0078) = 0.033 t
t = ln (0.0078)/-0.033
t = 147 hours
Learn more: brainly.com/question/6111443
Final volume is 400 mL
<span>The moles in MgSO4 is 0.00788 </span><span>mL
</span>
The new concentration is 0.197
Answer:
The more spread out their energy becomes
The hybridization of the central carbon compound CH4 tetrahedral is
SP^3 hybridization
In tetrahedral molecular geometry a central atom is located at the center with 4 substituent that are located at the corners of tetrahedron. Example in methane molecules is made up of b equally spaced sp^3 hybrid orbital forming bond angle of 109.5