The other dude is rude wrong
The correct answer is Dmitri Mendeleev
The radioactive decay obeys first order kinetics
the rate law expression for radioactive decay is
![ln\frac{[A_{0}]}{[A_{t}]}=kt](https://tex.z-dn.net/?f=ln%5Cfrac%7B%5BA_%7B0%7D%5D%7D%7B%5BA_%7Bt%7D%5D%7D%3Dkt)
Where
A0 = initial concentration
At = concentration after time "t"
t = time
k = rate constant
For first order reaction the relation between rate constant and half life is:
Let us calculate k
k = 0.693 / 72 = 0.009625 years⁻¹
Given
At = 0.25 A0
time = 144 years
So after 144 years the sample contains 25% parent isotope and 75% daughter isotopes**
Simply two half lives
Answer:
Option B. Both have a pH less than 7, but H3PO4 has a lower pH than HCl
Explanation:
Those are acid, so the pH would be < 7.
H₃PO₄ is a weak acid with 3 dissociations
HCl is a strong acid.
pH depends on [H]⁺
H₃PO₄ → 3H⁺ + PO₄⁻³
HCl → H⁺ + Cl⁻
If both acid, have the same concentration, [H⁺]H₃PO₄ > [H⁺]HCl, that's why the pH from the phosphoric will be lower.
Answer:
P³⁻ + Cl⁻ --> PCl₃
Explanation:
PCl₃: phosphorus trichloride. prefix in front of chloride is "tri"–meaning three.
All the layers should be kept until the experiment is complete.
<h3>What is extraction?</h3>
In chemistry, solvent extraction is accomplished by adding a sample containing the substance to be separated into a system of two solvents, an aqueous layer and an organic layer.
It is important to note that all the layers should be kept until the experiment is complete. No layer ought to be discarded before the work is completed.
Learn more about solvent extraction:brainly.com/question/11041092
