Answer:
67.6 years is the time the isotope take to decay from 0.900g to 0.170g
Explanation:
The radioactive decay follows first order law:
Ln [A] = -kt + ln[A]₀
<em>Where [A] is concentration after time t,</em>
<em>k is decay constant:</em>
<em>k = ln 2 / t(1/2)</em>
<em>k = ln2 / 28.1 years</em>
<em>k = 0.02467 years⁻¹</em>
<em>[A]₀ = Initial concentration.</em>
<em />
We can replace concentration and use the mass of the isotope:
Ln [A] = -kt + ln[A]₀
Ln [0.170g] = -0.02467 years⁻¹t + ln[0.900g]
-1.667 = -0.02467 years⁻¹t
t =
<h3>67.6 years is the time the isotope take to decay from 0.900g to 0.170g</h3>
Composting is not a technological way of improving air quality.
I hope this helps!
Answer: The concentration of hydrogen ion in the given solution is 
.
Explanation:
pOH of a solution is the negative logarithm of concentration of hydroxide ions.
Hence, if ![[OH^{-}]](https://tex.z-dn.net/?f=%5BOH%5E%7B-%7D%5D)
is 
then its pOH value is calculated as follows.
![pOH = -log [OH^{-}]\\= -log (3.5 \times 10^{-5})\\= 4.45](https://tex.z-dn.net/?f=pOH%20%3D%20-log%20%5BOH%5E%7B-%7D%5D%5C%5C%3D%20-log%20%283.5%20%5Ctimes%2010%5E%7B-5%7D%29%5C%5C%3D%204.45)
Now, the relation between pH and pOH is as follows.
pH + pOH = 14
pH + 4.45 = 14
pH = 14 - 4.45
= 9.55
And, pH is the negative logarithm of concentration of hydrogen ions. Hence, ![[H^{+}]](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D)
is calculated as follows.
![pH = -log [H^{+}]\\9.55 = -log [H^{+}]\\H^{+} = 2.81 \times 10^{-10}](https://tex.z-dn.net/?f=pH%20%3D%20-log%20%5BH%5E%7B%2B%7D%5D%5C%5C9.55%20%3D%20-log%20%5BH%5E%7B%2B%7D%5D%5C%5CH%5E%7B%2B%7D%20%3D%202.81%20%5Ctimes%2010%5E%7B-10%7D)
Thus, we can conclude that the concentration of hydrogen ion in the given solution is .
Answer:
Subtracting the number of protons from the atomic mass.
Answer:
ammonium chloride
Explanation:
Because NH is ammonium and Cl is chlorine
