It's in the periodic table.
See the attached picture. The number below 'Zn' is the molar mass. The closest answer choice is 65.38
Answer:
(a) 0.8 s
(b) t = 7.2 s
Explanation:
(a) Half life expression for second order kinetic is:
![t_{1/2}=\frac{1}{k[A_o]}](https://tex.z-dn.net/?f=t_%7B1%2F2%7D%3D%5Cfrac%7B1%7D%7Bk%5BA_o%5D%7D)
Where,
![[A_o]](https://tex.z-dn.net/?f=%5BA_o%5D)
is the initial concentration = 1.0 M
k is the rate constant = 1.25 M⁻¹s⁻¹
So,
Half life = 0.8 s
(b) Integrated rate law for second order kinetic is:
![\frac{1}{[A_t]} = \frac{1}{[A]_0}+kt](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B%5BA_t%5D%7D%20%3D%20%5Cfrac%7B1%7D%7B%5BA%5D_0%7D%2Bkt)
Where, ![[A_t]](https://tex.z-dn.net/?f=%5BA_t%5D)
is the final initial concentration
For 90% completion, 10% is left. so,
![[A_t]=\frac {10}{100}\times 1.0=0.1\ M](https://tex.z-dn.net/?f=%5BA_t%5D%3D%5Cfrac%20%7B10%7D%7B100%7D%5Ctimes%201.0%3D0.1%5C%20M)
So,
t = 7.2 s
Air pollution is the addition of impurities to the atmosphere. A physicist would be concerned because pollutants can reduce sunlight reaching the earth and this quantity, radiation, would fall under the scope of a physicist. Physicists might also be concerned with the absorption of heat by certain pollutants. They would be concerned with studying how much heat is absorbed by each molecule to ascertain the impact of the entire contamination in the atmosphere.
Explanation:
Once the earth's atmosphere was formed it really hasn't changed since, this is due to many reasons. Whatever created the earth's atmosphere (we don't know) has long disappeared, because of this the atmosphere cannot change, as there is nothing on earth that can change it (that we know of at least). Hopefully this helps.
