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)
1) Write the balanced chemical equation
2HCl + Na2 CO3 ----------> 2NaCl + H2CO3
2) Write the molar ratios:
2 mol HCl : 1 mol Na2CO3 : 2 mol NaCl : 1 mol H2CO3
3) Convert 0.15g of sodium carbonate to number of moles
3a) Calculate the molar mass of Na2CO3
Na: 2 * 23 g/mol = 46 g/mol
C: 12 g/mol =
O: 3 * 16 g/mol = 48 g/mol
molar mass = 46g/mol + 12g/mol + 48g/mol = 106 g/mol
3b.- Calculate the number of moles of Na2CO3
# moles = grams / molar mass = 0.15 g / 106 g/mol = 0.0014 mol Na2CO3
4) Calculate the number of moles of HCl from the molar proportion:
[0.0014 mol Na2CO3] * [2 mol HCl / 1 mol Na2CO3] = 0.0028 mol HCl
5) Calculate the volume of HCl from the definition of Molarity
Molarity, M = # moles / volume in liters
=> Volume in liters = # moles / M = 0.0028 mol / 0.1 M = 0.028 liters
0.028 liters * 1000 ml / liter = 28 ml.
Answer: 28 mililiters of 0.1 M HCl.
Some examples are like Russia, Egypt, China, Brazil
Answer:
When writing equation the mass on left side of equation must be equal to the mass on right side. True
Explanation:
The chemical reactions always follow the law of conservation of mass.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
Explanation:
This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
For example:
In photosynthesis reaction:
6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂
there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass because total mass is equal on both side of equation.
Answer:
2Sb^(+3) (aq) + 3S^(-2) (aq) = Sb_2•S_3
Explanation:
First of all, let us balance the equation to give;
2Sb(OH)3 (s) + 3Na2S (aq) = Sb2S3 + 3NaOH
Now, we can observe the presence of positive Sodium ions (Na+) and negative hydroxyl ions (OH-) on both left and right sides of the equation.
Now, the two ions will cancel out. These ions are not really involved in the overall reaction and thus do not require being written in the overall equation. Hence, the overall net ionic reaction can now be written as:
2Sb^(+3) (aq) + 3S^(-2) (aq) = Sb_2•S_3