Answer:
a) Check explanation for this
b)Rate law is ![Rate = \frac{k_{1}k_{4} }{k_{3}+ 2k_{4} } [H_{2} ]](https://tex.z-dn.net/?f=Rate%20%3D%20%5Cfrac%7Bk_%7B1%7Dk_%7B4%7D%20%20%7D%7Bk_%7B3%7D%2B%202k_%7B4%7D%20%20%7D%20%5BH_%7B2%7D%20%5D)
c) The rate does not depend on the concentration of CO₂
Explanation:
a) Elementary steps for the RWGS reaction:
- Dissociative adsorption of the H₂ Molecule
(Fast process)
- Reversible Reaction between CO₂ and H
(Fast Process)
- Slow dissociation of COOH into gaseous CO and absorbed OH
(Slow process)
- Fast hydrogenation of the OH to form H₂O
(Fast process)
b) Derivation of the rate law
We need to determine the rate law for H, OH and COOH because these are the intermediates for this reaction.
The steady state approximation is applied to a consecutive reaction with a slow first step and a fast second step (k1≪k2). If the first step is very slow in comparison to the second step, there is no accumulation of intermediate product.
Rate of consumption = Rate of production
For COOH:
Using steady state approximation
![\frac{d[COOH]}{dt} = 0](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5BCOOH%5D%7D%7Bdt%7D%20%3D%200)
![k_{2} [CO_{2} ][H] = k_{3} [COOH] k_{4} [COOH]\\](https://tex.z-dn.net/?f=k_%7B2%7D%20%5BCO_%7B2%7D%20%5D%5BH%5D%20%3D%20k_%7B3%7D%20%5BCOOH%5D%20k_%7B4%7D%20%5BCOOH%5D%5C%5C)
![[COOH] = \frac{k_{2} [CO_{2} ][H]}{k_{3}k_{4} } \\](https://tex.z-dn.net/?f=%5BCOOH%5D%20%3D%20%5Cfrac%7Bk_%7B2%7D%20%5BCO_%7B2%7D%20%5D%5BH%5D%7D%7Bk_%7B3%7Dk_%7B4%7D%20%20%7D%20%5C%5C)
For H:
![\frac{d[H]}{dt} = 0](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5BH%5D%7D%7Bdt%7D%20%3D%200)
![k_{1}[H_{2}] = k_{2}[CO_{2} [H]+k_{5} [ OH][H]](https://tex.z-dn.net/?f=k_%7B1%7D%5BH_%7B2%7D%5D%20%3D%20k_%7B2%7D%5BCO_%7B2%7D%20%5BH%5D%2Bk_%7B5%7D%20%5B%20OH%5D%5BH%5D)
![[H]= \frac{k_{1}[H_{2}] }{k_{5}[OH] +k_{2}[CO_{2}]}\\](https://tex.z-dn.net/?f=%5BH%5D%3D%20%5Cfrac%7Bk_%7B1%7D%5BH_%7B2%7D%5D%20%20%7D%7Bk_%7B5%7D%5BOH%5D%20%2Bk_%7B2%7D%5BCO_%7B2%7D%5D%7D%5C%5C)
For OH:
![\frac{d[OH]}{dt} = 0](https://tex.z-dn.net/?f=%5Cfrac%7Bd%5BOH%5D%7D%7Bdt%7D%20%3D%200)
![k_{4} [COOH] = k_{5} [OH][H]\\\k[OH] = \frac{k_{4} [COOH]}{k_{5} H}\\](https://tex.z-dn.net/?f=k_%7B4%7D%20%5BCOOH%5D%20%3D%20k_%7B5%7D%20%5BOH%5D%5BH%5D%5C%5C%5Ck%5BOH%5D%20%3D%20%5Cfrac%7Bk_%7B4%7D%20%5BCOOH%5D%7D%7Bk_%7B5%7D%20H%7D%5C%5C)
The rate of the overall reaction is determined by the slowest step of the reaction. The slowest process is the dissociation of COOH
Therefore the overall rate of reaction is:
![Rate = k_{4} [COOH]\\](https://tex.z-dn.net/?f=Rate%20%3D%20k_%7B4%7D%20%5BCOOH%5D%5C%5C)
![Rate = k_{4} \frac{k_{2} [CO_{2} ][H]}{k_{3}k_{4} }\\Rate = k_{4} \frac{k_{2}[CO_{2}]\frac{k_{1}[H_{2}] }{k_{5}[OH] +k_{2}[CO_{2}]} }{k_{3}k_{4}}\\Rate = k_{4} \frac{k_{2}[CO_{2}]\frac{k_{1}[H_{2}] }{k_{5}\frac{k_{4}COOH }{k_{5}H } +k_{2}[CO_{2}]} }{k_{3}k_{4}}](https://tex.z-dn.net/?f=Rate%20%3D%20k_%7B4%7D%20%20%5Cfrac%7Bk_%7B2%7D%20%5BCO_%7B2%7D%20%5D%5BH%5D%7D%7Bk_%7B3%7Dk_%7B4%7D%20%20%7D%5C%5CRate%20%3D%20k_%7B4%7D%20%20%5Cfrac%7Bk_%7B2%7D%5BCO_%7B2%7D%5D%5Cfrac%7Bk_%7B1%7D%5BH_%7B2%7D%5D%20%20%7D%7Bk_%7B5%7D%5BOH%5D%20%2Bk_%7B2%7D%5BCO_%7B2%7D%5D%7D%20%20%7D%7Bk_%7B3%7Dk_%7B4%7D%7D%5C%5CRate%20%3D%20k_%7B4%7D%20%20%5Cfrac%7Bk_%7B2%7D%5BCO_%7B2%7D%5D%5Cfrac%7Bk_%7B1%7D%5BH_%7B2%7D%5D%20%20%7D%7Bk_%7B5%7D%5Cfrac%7Bk_%7B4%7DCOOH%20%7D%7Bk_%7B5%7DH%20%7D%20%20%2Bk_%7B2%7D%5BCO_%7B2%7D%5D%7D%20%20%7D%7Bk_%7B3%7Dk_%7B4%7D%7D)
Simplifying the equation above, the rate law becomes
![Rate = \frac{k_{1}k_{4} }{k_{3}+ 2k_{4} } [H_{2} ]](https://tex.z-dn.net/?f=Rate%20%3D%20%5Cfrac%7Bk_%7B1%7Dk_%7B4%7D%20%20%7D%7Bk_%7B3%7D%2B%202k_%7B4%7D%20%20%7D%20%5BH_%7B2%7D%20%5D)
c) It is obvious from the rate law written above that the rate of the RWBG reaction does not depend on the concentration of CO₂
Answer:
a) The minimum acceptable value is 387.5 HV using Vickers hardness test.
b) The minimum acceptable value is 39.4 HRC using Rockwell C hardness test.
Explanation:
To get the tensile strength of a material from its hardness, we multiply it by an empirical constant that depends on things like yield strength, work-hardening, Poisson's ratio and geometrical factors. The incidence of cold-work varies this relationship.
According to DIN 50150 (a conversion table for hardness), the constant for Vickers hardness is ≈ 3.2 (an empirical approximate):
According to DIN 50150, the constant for Rockwell C hardness test is ≈31.5 around this values of tensile strength:
I say A because, During a Biomechanical assessment we are able to track even further up the body, to lower back pain caused by the feet. Biomechanics is the tool that understands human movement and has also become hugely popular amongst sports athletes as it is used to enhance athletic performance and prevent injury, too.
Answer:
manning's coefficient is 0.0357
Explanation:
Given:
Velocity of flow, v = 12 m/s
Width of the channel, b = 6 m
Depth of the channel, d = 2 m
bed slope, s = 0.001
mean velocity of flow, V = 1 m/s
now, the velocity is given as:

where,
n is the manning's coefficient
R is hydraulic mean depth
R = (Area of the channel) / (wetted Perimeter of the channel)
now,
R = (2 × 6) / ((2 × 2) + 6)
or
R = 12 / 10 = 1.2 m
now, on substituting the values in the equation for velocity, we get

or

or
n = 0.0357
hence, the value of manning's coefficient is 0.0357
Answer:
Modulus of resilience will be 
Explanation:
We have given yield strength 
Elastic modulus E = 104 GPa
We have to find the modulus
Modulus of resilience is given by
Modulus of resilience
, here
is yield strength and E is elastic modulus
Modulus of resilience