Answer:
Explanation:
From the given information:
A → B k₁
B → A k₂
B + C → D k₃
The rate law = ![\dfrac{d[D]}{dt}=k_3[B][C] --- (1)](https://tex.z-dn.net/?f=%5Cdfrac%7Bd%5BD%5D%7D%7Bdt%7D%3Dk_3%5BB%5D%5BC%5D%20---%20%281%29)
![\dfrac{d[B]}{dt}=k[A] -k_2[B] -k_3[B][C]](https://tex.z-dn.net/?f=%5Cdfrac%7Bd%5BB%5D%7D%7Bdt%7D%3Dk%5BA%5D%20-k_2%5BB%5D%20-k_3%5BB%5D%5BC%5D)
Using steady-state approximation;
![\dfrac{d[B]}{dt}=0](https://tex.z-dn.net/?f=%5Cdfrac%7Bd%5BB%5D%7D%7Bdt%7D%3D0)
![k_1[A]-k_2[B]-k_3[B][C] = 0](https://tex.z-dn.net/?f=k_1%5BA%5D-k_2%5BB%5D-k_3%5BB%5D%5BC%5D%20%3D%200)
![[B] = \dfrac{k_1[A]}{k_2+k_3[C]}](https://tex.z-dn.net/?f=%5BB%5D%20%3D%20%5Cdfrac%7Bk_1%5BA%5D%7D%7Bk_2%2Bk_3%5BC%5D%7D)
From equation (1), we have:
![\mathbf{\dfrac{d[D]}{dt}= \dfrac{k_3k_1[A][C]}{k_2+k_3[C]}}](https://tex.z-dn.net/?f=%5Cmathbf%7B%5Cdfrac%7Bd%5BD%5D%7D%7Bdt%7D%3D%20%5Cdfrac%7Bk_3k_1%5BA%5D%5BC%5D%7D%7Bk_2%2Bk_3%5BC%5D%7D%7D)
when the pressure is high;
k₂ << k₃[C]
![\dfrac{d[D]}{dt} = \dfrac{k_3k_1[A][C]}{k_3[C]}= k_1A \ \ \text{first order}](https://tex.z-dn.net/?f=%5Cdfrac%7Bd%5BD%5D%7D%7Bdt%7D%20%3D%20%5Cdfrac%7Bk_3k_1%5BA%5D%5BC%5D%7D%7Bk_3%5BC%5D%7D%3D%20k_1A%20%5C%20%5C%20%20%5Ctext%7Bfirst%20order%7D)
k₂ >> k₃[C]
![\dfrac{d[D]}{dt} = \dfrac{k_3k_1[A][C]}{k_2}= \dfrac{k_1k_3}{k_2}[A][C] \ \ \text{second order}](https://tex.z-dn.net/?f=%5Cdfrac%7Bd%5BD%5D%7D%7Bdt%7D%20%3D%20%5Cdfrac%7Bk_3k_1%5BA%5D%5BC%5D%7D%7Bk_2%7D%3D%20%5Cdfrac%7Bk_1k_3%7D%7Bk_2%7D%5BA%5D%5BC%5D%20%5C%20%5C%20%20%5Ctext%7Bsecond%20order%7D)
Answer:
See explanation
Explanation:
Air contains a mixture of several molecules and compounds such as oxygen and carbon dioxide.
Answer:
2. All the naturally occurring isotopes of Mg.
Explanation:
You want to know the atomic mass of the magnesium you use in the lab. That’s “natural” magnesium. So, you must use the weighted average of all the naturally occurring isotopes in natural Mg.
1. and 3. are <em>wrong</em>. You won’t get the correct mass for natural Mg if you use only the artificial isotopes for your calculation.
4. is <em>wrong</em>. You must use all the naturally occurring isotopes. The two most abundant isotopes of Mg account for only 90 % of the atoms. If you ignore the other 10 %, your calculation will be wrong.
