To remain successful and competitive, e-Commerce has relied on all the SCOR model functions.
The SCOR (Supply Chain Operations Reference) model is a management tool for addressing, improving, and communicating supply chain management decisions. E-commerce platforms, to ensure their competitiveness, rely on all these functions. 'Plan' involves strategic planning for managing resources. 'Source' encompasses the procurement of goods and services. 'Make' pertains to the manufacturing or assembly of products. 'Deliver' (or logistics function) involves warehousing and order fulfillment. 'Return' relates to managing returns for defective or excess products. 'Enable' includes the management and support tasks like HR, Finance, IT services, etc. E-commerce businesses leverage these functions for efficient and effective supply chain management, thereby ensuring their success and competitiveness.
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The pyramids in Egypt are cited as an ancient world wonder. What is the main
reason that the pyramids are important to the study of engineering?
The pyramids are important to the study of engineering because they were some of the first structures built using engineering principles. The pyramids are an example of how engineering can be used to create amazing structures.
What is pyramid?
A pyramid is a structure with triangular exterior surfaces that converge to a single step at the summit, giving the shape the shape of a pyramid in the geometric sense. A pyramid's base can be trilateral, quadrilateral, or any polygon shape. A pyramid, as a result, has at least three exterior triangle surfaces. A typical variant is the square pyramid, which has a square base and four triangular exterior surfaces. The design of a pyramid, with the majority of the weight closer to the bottom and the pyramidion at the apex, means that less material will be pushed down from above. This weight distribution enabled early civilizations to build stable massive constructions.
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technician a says that the injector supply lines must be replaced if they are removed. technician b says that the supply lines can be reused. which technician is correct?
The injector supply lines must be replaced if they are removed. So, what is said by technician A is correct.
Injector refers to a device that is used to inject liquid fuel into an internal-combustion engine. The injector can also used for describing an apparatus to injcet feed water into a boiler. The injector supply lines must be replaced if they are removed. The injector can be used as a spray nozzle to break up the fuel into a fine spray - it doesn't always control the fuel flow. There are three general kind of injection systems on the market:
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What are the maximum weights for single, tandem and 5-axle combinations?
Identify the transformation. Note: you can only submit this question once for marking. translation rotation shear projection none of the above
Answer:
The answer is "shear".
Explanation:
Every transformation could be shown by some kind of conventional matrix.
Its standard matrices of shape k here could be any real value enabling shear transformation to parallel to the y axis.
\(\left[\begin{array}{cc}1&0\\k&1\\\end{array}\right]\)
This coefficient matrix A is the standard matrix during transformation. With the use of a the transformation could be entered into T(x)=Ax
And standard transfer function is standard.
\(\left[\begin{array}{cc}1&0\\6&1\\\end{array}\right]\)
The matrix in the form of the shear matrix.
The density and associated percent crystallinity for two poly(ethylene terephthalate) materials are as follows:
The density and associated percent crystallinity f(g/cm3) Crystallinity (%)
1.408 74.3
1.343 31.2
(a) Compute the density of totally crystalline poly(ethylene terephthalate).
(b) Compute the density of totally amorphous poly(ethylene terephthalate).
(c) Determine the percent crystallinity of a specimen having a density of 1.382 g/cm3.
The percent crystallinity of the specimen with a density of 1.382 g/cm^3 is approximately 85.5%.
To compute the density of totally crystalline poly(ethylene terephthalate) (PET), we can use the density and percent crystallinity values given for the material.
(a) Compute the density of totally crystalline PET:
Density of totally crystalline PET = Density / (1 - Percent Crystallinity / 100)
Density = 1.408 g/cm^3
Percent Crystallinity = 74.3%
Density of totally crystalline PET = 1.408 / (1 - 74.3 / 100)
Density of totally crystalline PET = 1.408 / (1 - 0.743)
Density of totally crystalline PET = 1.408 / 0.257
Density of totally crystalline PET ≈ 5.484 g/cm^3
(b) Compute the density of totally amorphous PET:
Density of totally amorphous PET = Density / (1 + Percent Crystallinity / 100)
Density = 1.343 g/cm^3
Percent Crystallinity = 31.2%
Density of totally amorphous PET = 1.343 / (1 + 31.2 / 100)
Density of totally amorphous PET = 1.343 / (1 + 0.312)
Density of totally amorphous PET = 1.343 / 1.312
Density of totally amorphous PET ≈ 1.023 g/cm^3
(c) Determine the percent crystallinity of a specimen having a density of 1.382 g/cm^3:
Percent Crystallinity = (Density of totally crystalline PET - Density of the specimen) / (Density of totally crystalline PET - Density of totally amorphous PET) * 100
Density of the specimen = 1.382 g/cm^3
Density of totally crystalline PET = 5.484 g/cm^3
Density of totally amorphous PET = 1.023 g/cm^3
Percent Crystallinity = (5.484 - 1.382) / (5.484 - 1.023) * 100
Percent Crystallinity ≈ 85.5%
Therefore, the percent crystallinity of the specimen with a density of 1.382 g/cm^3 is approximately 85.5%.
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If the contact surface between the 20-kg block and the ground is smooth, determine the power of force F when t = 4 s. Initially, the block is at rest
Answer:
115.2 W
Explanation:
The computation is shown below:
As we know that
Power = F . v
\(F_H = F cos \theta\)
\(F_H = 30 \frac{4}{5}\)
\(F_H = 24N\)
Now we solve for V
\(V = V_0 + at\) a = 24N ÷ 20Kg
But V_0 = 0 a = 1.2 m/s^2
F_H = ma V = 0 + (1.2) (4)
a = F_H ÷ m V = 4.8 m/s
Therefore
Power = F_Hv
= (24) (4.8)
= 115.2 W
By applying the above formuals we can get the power
Which of the following wouldn't be pictured on a fan motor's ladder logic diagram? A. Auxiliary contacts B. two Push-button control C. Boiler D. Mixing chamber
Answer:
c
Explanation:
:)
A well-insulated heat exchanger has one line with 2 kg/s of air at 125 kPa and 1000 K entering, and leaving at 100 kPa and 400 K. The other line has 0.5 kg/s water entering at 200 kPa and 20 °C, and leaving at 200 kPa. Calculate the exit temperature of the water and the total rate of entropy generation?
Answer:
120°CExplanation:
Step one:
given data
T_{wi} = 20^{\circ}C
T_{Ai}=1000K
T_{Ae}= 400kPa
P_{Wi}=200kPa
P_{Ai}=125kPa
P_{We}=200kPa
P_{Ae}=100kPa
m_A=2kg/s
m_W=0.5kg/s
We know that the energy equation is
\(m_Ah_{Ai}+m_Wh_W=m_Ah_{Ae}+m_Wh_{We}\)
making \(h_{We}\) the subject of formula we have
\(h_{We}=h_{Wi}+\frac{m_A}{mW}(h_A-h_{Ae})\)
from the saturated water table B.1.1 , corresponding to \(T_{wi}= 20c\)
\(h_{Wi}=83.94kJ/kg\)
from the ideal gas properties of air table B.7.1 , corresponding to T=1000K
the enthalpy is:
\(h_{Ai}=1046.22kJ/kg\)
from the ideal gas properties of air table B.7.1 corresponding to T=400K
\(h_{Ae}=401.30kJ/kg\)
Step two:
substituting into the equation we have
\(h_{We}=h_{Wi}+\frac{m_A}{mW}(h_A-h_{Ae})\)
\(h_{We}=83.94+\frac{2}{0.5}(2046.22-401.30)\\\\h_{We}=2663.62kJ/kg\)
from saturated water table B.1.2 at \(P_{We}=200kPa\) we can obtain the specific enthalpy:
\(h_g=2706.63kJ/kg\)
we can see that \(h_g>h_{Wi}\), hence there are two phases
from saturated water table B.1.2 at \(P_{We}=200kPa\)
\(T_{We}=120 ^{\circ} C\)
Which of the following is an implication of low
variety?
A. low unit cost
B. flexibility needed
C. high complexity
D. matching customers specific needs
PLEASE EXPLAIN WHICH IS CORRECT WITH EXPLANATION
The correct option for the implication of low variety is B) Flexibility needed. Variety refers to the number of different products, services, or activities that an organization offers. High variety means that a company offers a wide variety of products or services, while low variety means that a company provides a limited range of products or services.
One of the implications of low variety is that customers have limited options. They are restricted to purchasing only those goods and services that the company offers, which may not match their requirements or preferences. This may lead to losing customers to rivals who offer a greater variety of goods and services.
In the case of low variety, it is critical to have the required flexibility. Customers may ask for certain specific goods or services that are not provided by the company. To meet customer requirements, the company should be adaptable and able to rapidly respond to customer requests by expanding its product line. As a result, low variety necessitates the need for flexibility.
The other given options are not valid. Low unit cost is not related to low variety. Unit cost may be affected by economies of scale and other factors, but it is not directly related to variety. High complexity is not related to low variety as well. As the range of goods and services offered by the company increases, the complexity of the company's operations and management also increases. Matching customers' specific needs is partially correct because the company cannot match customer specific needs in low variety. In low variety, the company has a limited range of goods and services, so it is not possible to fulfill all the customers’ specific needs.
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If a circuit produces a phase shift of 45 degrees between the voltage and current curves and the apparent power is 100 VA, what is the TRUE power in the circuit?
50 W
70.7 VA
70.7 W
100 A
The true power is obtained as 70.7 VA.
What is the true power?We define the power a the rate of doing work, we know that the power in a circuit is the product of the current and the voltage. In this case, we want to find the true power thus we have to involve the use of the phase shift in degrees.
Thus;
True power = PcosΦ
P = 100 VA
Φ = 45 degrees
True power = 100 VA * cos 45 degrees
True power = 70.7 VA
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What traffic sign is this
Answer:
Stop Sign
Explanation:
It's red and shaped like an octogon
What is the safe psi pressure for acetylene
Answer:
15psig
Explanation:
The oil pump is mounted in which part of transmission?
Back of transmission
Front of transmission
Left of transmission
Right of transmission
In the context of electronics, the term "ground" is often used to refer to:
1: the negative battery terminal
2:the breadboard
3:the circuit diagram
4:the components
Which one is the answer
Answer:
1: the negative battery terminal
Explanation:
When we design and develop an electrical circuit in electrical and electronics engineering, it is important that we define a reference point for all electronic signals from which we can measure voltage. Although, the voltage passing through a reference point in an electrical circuit is typically 0 Volts.
Also, a ground is a common return path in an electrical circuit for the current flowing through the circuit.
When working on a direct current (DC) circuit that is mainly operated using a battery, the negative terminal of the battery would be the ground (reference point) for all the components connected to the electrical circuit.
Hence, in the context of electronics, the term "ground" is often used to refer to the negative battery terminal.
Which two statements about professional technical jobs in the energy industry are correct?
A. Energy careers offer limited prospects.
B. Certifications are often necessary to be employed in the energy sector.
C. Continuing education and certifications must be done in a classroom setting.
D. Continuing education is important to have a long-term energy career.
E. Energy technology is static.
Answer: the answer is B and D
Explanation:
8.28 Water is the working fluid in an ideal Rankine cycle with superheat and reheat. Steam enters the first-stage turbine at 1400 lbf/in.2 and 10008F, expands to a pressure of 350 lbf/in.2, and is reheated to 9008F before entering the secondstage turbine. The condenser pressure is 2 lbf/in.2 The net power output of the cycle is 1 3 109 Btu/h. Determine for the cycle (a) the mass flow rate of steam, in lb/h. (b) the rate of heat transfer, in Btu/h, to the working fluid passing through the steam generator. (c) the rate of heat transfer, in Btu/h, to the working fluid passing through the reheater. (d) the thermal efficiency.
Answer:
Betbtybrbytntrnyrnrynunjhjhnthnnhtnnthnhtnnhnhrnntnthhnhnhtnthn
Explanation:
Cell phones require powerful batteries in orde to work effectively. Which activity is best described as an engineering endeavor related to cell phone batteries
A 2.4-in diameter soap bubble is to be enlarged by blowing air into it. Taking the surface tension of solution to be 0.0027 ⁄, determine the work input (in ∙ ) required to inflate the bubble to a diameter of 2.7- in.
The work input required to inflate the bubble to a diameter of 2.7- in is 9.12 x 10⁻⁷.
What is work done?When an object is moved over a specific distance by an external force, the quantity of energy delivered to it is known as work.
Change in surface area
4π [2.7² - 2.4]
4π [7.29 -5.76]
19.22 m² = 19.22 x 0.083 = 0.132
Work done = surface tension x change into area
T x 2A
0.0027 x 2 x 0.132 lbf
0.00071 lbt. H
0.0007 x 0.00128 Bt
9.12 x 10⁻⁷
Therefore, the work input required to inflate the bubble to a diameter of 2.7- in is 9.12 x 10⁻⁷.
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Assume that the electrons in a material follow the Fermi-Dirac distribution function and assume that EF is 0.3eV below EC. Determine the temperature at which the probability of an electron occupying an energy state at E=(EC+0.025)eV is 8×10−6.
Assuming that the electrons in a material follow the Fermi-Dirac distribution function and EF is 0.3eV below EC, the temperature at which the probability of an electron occupying an energy state at E=(EC+0.025)eV is 8×\(10^{-6}\) is 271.74 K.
A mathematical depiction of the probability distribution of the energy of the quantum states that electrons can reside in at a specific temperature is the Fermi-Dirac probability function.
It explains what happens to the electrons within metal solids as their temperature rises. The Fermi Level Formula is - k=1.38×10-23 J/K=8.62×10-5 eV/K. The detailed solution is attached below.
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The frame supports the loading shown. The pin at A has a diameter of 0.25 in. If it is subjected to double shear, determine the average shear stress in the pin. -2 ft -2 ft E 3 ft 600 lb В B
The average shear stress on the pin at position A is roughly 30552 psi.
With the average shear stress, how can I calculate the maximum shear stress?What is the formula for maximal shear stress? V*Q / I*b is the formula for computing maximum shear stress. Simply expressed, this is 12*V / 8bh. Shear force, cross-sectional breadth, and height are all denoted by the letters V, B, and h respectively.
The stress equation is what.In terms of stress (elastic modulus – strain). In terms of stress (elastic modulus – strain). A dimensional study of this connection reveals that the elastic modulus has the same physical unit as stress since strain has no dimensions.
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A shaft of a circular cross section is supported by two housings at B and C. The shaft
is subjected to static loads: concentrated force N applied by gear D and an applied torque T. The yielding strength of the shaft is Sy, and the diameter of the shaft is d. For circular cross sections, | = nd*/64, J = md*/32. The length of the shaft is L. Transverse shear stress is ignored here.
1) Draw the bending moment diagram of the shaft. Specify the location of the weakest (most dangerous) cross section A on bending moment diagram.
2) Draw the weakest point(s) on cross section A.
3) Determine the von-Mises stress at the weakest point(s).
4) Determine the factor of safety n based on Distortion Energy Theory.
Answer:
1) The bending moment diagram of the shaft is shown in Figure 1. The weakest cross section A is located at the point where the bending moment is maximum.
2) The weakest point on cross section A is located at the point where the bending moment is maximum.
3) The von-Mises stress at the weakest point is given by:
σ = M/I
where M is the bending moment and I is the moment of inertia of the cross section.
4) The factor of safety n is given by:
n = Sy/σ
where Sy is the yield strength of the shaft and σ is the von-Mises stress at the weakest point.
Explanation:
Hope this helps!
explain how to achieve proper drive pinion gear bearing preload
Answer: The correct way to achieve proper drive pinion gear bearing preload is to torque the pinion nut to the manufacturer’s specifications and then check for preload.
Explanation: Typical starting points for torque specifications are 55 lb-ft for 3/8-inch bolts/nuts, 75 lb-in for 7/16-inch bolt/nuts, and 125 lb-in for 1/2-inch nuts/bolts. Once the nut is properly torqued, check for preload by tapping the end of the pinion gear with a punch to ensure the races are fully seated, shake it to evaluate for excessive play.
Pinion bearings are bearings that support the weight of the drive shaft and transfer power from the differential to the wheels. Preload is the tension that is put on a bearing. In the case of pinion bearings, preload takes place in the form of a collapsible spacer that stays between the bearings. The required amount of tension is obtained by adjusting the space manually.
Other ways to achieve proper drive pinion gear bearing preload include using a crush sleeve or shims. Crush sleeves are used in place of spacers and are designed to be crushed when the pinion nut is tightened. This crushes the sleeve and creates tension on the bearings. Shims can also be used to adjust the space between bearings.
Common problems with drive pinion gear bearing preload include over-tightening or under-tightening of the pinion nut, which can lead to damage or failure of the bearings. It is important to follow manufacturer specifications when torquing the pinion nut and checking for preload.
Hope this helps, and have a great day!
Tech A says that engines in most RWD vehicle are removed from the top. Tech B says that before an engine fails, there are usually warning signs such as dash warning lights indicating low oil pressure, high operating temperature, or abnormal engine noises. Who is correct
Answer: Both A and B
Explanation: because they are both true
What are some of the advantages of working in preconstruction?
locate the centroid of the shaded area between the two curves
9514 1404 393
Answer:
(x, y) = (5.76, 1 5/7)
Explanation:
The location of the centroid in the x-direction is the ratio of the first moment of area about the y-axis to the total area. Similarly, the y-coordinate of the centroid is the first moment of area about the x-axis, divided by the area.
For the moment about the y-axis, we can define a differential of area as ...
dA = (y2 -y1)dx
where y2 = √(x/k2) and y1 = k1·x^3
The distance of that area from the y-axis is simply x.
So, the x-coordinate of the centroid is ...
\(\displaystyle c_x=\frac{a_x}{a}=\frac{\int{x\cdot dA}}{\int{dA}}\\\\a_x=\int_0^{12}{x(k_2^{-1/2}\cdot x^{1/2}-k_1x^3)}\,dx=\frac{2}{5k_2^{1/2}}\cdot12^{5/2}-\frac{k_1}{5}12^5\\\\a=\int_0^{12}{(k_2^{-1/2}\cdot x^{1/2}-k_1x^3)}\,dx=\frac{2}{3k_2^{1/2}}\cdot12^{3/2}-\frac{k_1}{4}12^4\\\)
For k1 = 4/12^3 and k2=12/4^2, these evaluate to ...
\(a_x=115.2\\a=20\\c_x=5.76\)
The y-coordinate of the centroid requires we find the distance of the differential of area from the x-axis. We can use (y2 +y1)/2 for that purpose. Then the y-coordinate is ...
\(\displaystyle c_y=\frac{a_y}{a}\\\\a_y=\int_0^{12}{(\frac{y_2+y_1}{2}(y_2-y_1))}\,dx=\frac{1}{2}\int_0^{12}{(\frac{x}{k_2}-(k_1x^3)^2)}\,dx\\\\a_y=\frac{12^2}{4k_2}-\frac{k_1^212^7}{14}=\frac{240}{7}\\\\c_y=\frac{12}{7}\approx1.7143\)
The centroid of the shaded area is ...
(x, y) = (5.76, 1 5/7)
A square plate of titanium is 12cm along the top, 12cm on the right side, and 5mm thick. A normal tensile force of 15kN is applied to the top side of the plate. A normal tensile force of 20kN is applied to the right side of the plate. The elastic modulus, E, is 115 GPa for titanium.If the left and bottom edges of the plate are fixed, calculate the normal strain and elongation of both the TOP and RIGHT side of the plate.
Answer:
\(X_t=2.17391304*10^{-4}\)
\(X_r=2.89855072*10^{-4}\)
\(e_t=0.0026\)
\(e_r=0.0035\)
Explanation:
From the question we are told that:
Dimension \(12*12\)
Thickness \(l_t=5mm=5*10^-3\)
Normal tensile force on top side \(F_t= 15kN\)
Normal tensile force on right side \(F_r= 20kN\)
Elastic modulus, \(E=115Gpap=>115*10^9\)
Generally the equation for Normal Strain X is mathematically given by
\(X=\frac{Force}{Area*E}\)
Therefore
For Top
\(X_t=\frac{Force_t}{Area*E}\)
Where
\(Area=L*B*T\)
\(Area=12*10^{-2}*5*10^{-3}\)
\(Area=6*10^{-4}\)
\(X_t=\frac{15*10^3}{6*10^{-4}*115*10^9}\)
\(X_t=2.17391304*10^{-4}\)
For Right side\(X_r=\frac{Force_r}{Area*E}\)
Where
Area=L*B*T
\(Area=12*10^{-2}*5*10^{-3}\)
\(Area=6*10^{-4}\)
\(X_r=2.89855072*10^{-4}\)
\(X_r=2.89855072*10^{-4}\)
Generally the equation for elongation is mathematically given by
\(e=strain *12\)
For top
\(e_t=2.17391304*10^{-4}*12\)
\(e_t=0.0026\)
For Right
\(e_r=2.89855072*10^{-4} *12\)
\(e_r=0.0035\)
If water is inserted between plates of a capacitor, what do you think will happen?
Answer:
We well know that water is a conductor of charges. So, when it is between capacitor plates, the charges flow from positive plate to negative plate hence discharge occurs
Explanation:
\({}\)
technician a says that an analog scope can store the waveform for viewing later. technician b says that the trigger level has to be set on most scopes to be able to view a changing waveform. which technician is correct?
Both Technician A and Technician B are correct. An analog oscilloscope can store the waveform for viewing later, and the trigger level must be set on most scopes to be able to view a changing waveform.
An oscilloscope is a device used to measure and analyze electrical signals in oscillatory form. It consists of a display, vertical and horizontal amplifiers, and a trigger. The trigger is used to capture a specific point of the waveform and synchronize it with the display. It is important to set the trigger level correctly in order to get an accurate reading of the waveform.
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The starting workpiece in steel hot rolling of plate and sheet stock is which of the following (one best answer): (a) bar stock, (b) billet, (c) bloom, (d) slab, or (e) wire stock?
The starting workpiece in steel hot rolling of plate and sheet stock is (d) slab, as it provides the most suitable form for this process.
The steel hot rolling process involves converting a starting workpiece into a thinner and longer sheet or plate stock. This process is widely used in industries such as automotive, construction, and manufacturing. The starting workpiece in steel hot rolling can vary depending on the desired final product. However, there is one best answer to the question of which starting workpiece is used for plate and sheet stock. The correct answer is (d) slab. Slabs are rectangular blocks of steel that have been casted in a mold and allowed to cool. They are then reheated and rolled into thinner sheets or plates using a hot rolling mill.
In summary, the starting workpiece for steel hot rolling of plate and sheet stock is a slab. This is an important step in the manufacturing process that allows for the creation of high-quality steel products used in various industries.
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Consider the titration of 100.0 mL of 0.200 M CH3NH2 by 0.100 M HCl.
For each volume of HCl added, decide which of the components is a major species after the HCl has reacted completely.
Kb for CH3NH2 = 4.4 x 10-4.
What species are present based off what is being added?
200.00 mL HCl added
yes no H+
yes no H2O
yes no Cl-
yes no CH3NH2
yes no CH3NH3+
300.00 mL HCl added
yes no H+
yes no H2O
yes no Cl-
yes no CH3NH2
yes no CH3NH3+
Calculate the pH at the equivalence point for this titration?
Answer:
The answers are in the explanation. The pH is 5.91
Explanation:
The CH3NH2 reacts with HCl as follows:
CH3NH2 + HCl → CH3NH3⁺ + Cl⁻
When 200mL of HCl are added, the moles of CH3NH2 and HCl are reacting completely producing CH3NH3+ and Cl-. That means the species present are:
no H+. All reacted
yes H2O. Because the water is present in the solutions of HCl and CH3NH2
yes Cl-. Is a product of the reaction
Yes CH3NH2. Is consumed in the reaction but comes from the equilibrium of CH3NH3+
yes CH3NH3+. Is the other product of the reaction. MAJOR SPECIES
When 300.00mL of HCl are added, 100mL are in excess:
yes H+. Is in excess: H+ + Cl- = HCl in water. MAJOR SPECIES. Determine the pH of the solution.
yes H2O. Is present because the reactants are diluted.
yes Cl-. Is a product of reaction and comes from HCl.
Yes CH3NH2. The reactant is over but comes from the equilibrium of CH3NH3+
yes no CH3NH3+. Yes. Is a product and remains despite HCl is in excess.
To find the pH:
At equivalence point the ion that determines pH is CH3NH3+. Its concentration is:
0.100L * (0.200mol/L) = 0.0200 moles / 0.300L = 0.0667M CH3NH3+
The equilibrium of CH3NH3+ is:
Ka = Kw/kb = 1x10-14/4.4x10-4 = 2.273x10-11 = [H+] [CH3NH2] / [CH3NH3+]
As both [H+] [CH3NH2] comes from the same equilibrium:
[H+] = [CH3NH2] = X
2.273x10-11 = [X] [X] / [0.0667M]
1.5159x10-12 = X²
X = 1.23x10-6M = [H+]
As pH = -log [H+]
pH = 5.91
The pH at the equivalent point for this titration is "5.91".
pH Calculation:\(CH_3NH_2 = 0.200\ M\\\\ \text{volume} = 100.0\ mL = 0.100\ L\\\\HCl = 0.100\ M\\\\\)
We must now quantify the pH well at the equivalence point.
We know that even at the point of equivalence, moles of acid and moles of the base are equivalent. As such, first, we must calculate the number of moles of the given base.
Calculating the Moles in \(CH_3NH_2 = 0.200\ M \times 0.100\ L = 0.0200\ moles\)
Calculating the Moles in \(HCl = 0.0200 \ moles\)
Calculating the volume of \(HCl\):
\(\to \text{Molarity} = \frac{ \text{moles}}{\text{volume \ (L)}} \\\\\to \text{Volume} = \frac{\text{moles}}{\text{molarity}}\\\\\)
\(= \frac{0.0200 \ moles}{ 0.100\ M}\\\\= 0.200 \ L\\\\= 200 \ mL\\\\\)
Calculating the reaction among the acid and base:
\(CH_3NH_2 + HCl \longrightarrow CH_3NH_3^{+} + Cl^-\)
\(0.0200 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ 0.0200 \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ 0.0200\)
Therefore the conjugate acid of the bases exists at the standard solution.
Then we must calculate the new molar mass of \(CH_3NH_3^+\).
Total volume\(= 100 + 200 = 300\ mL = 0.300\ L\)
\([CH_3NH_3^+] = \frac{0.0200\ mole}{ 0.300\ L}= 0.0667\ M\)
Using the ICE table
\(CH_3NH_3^+ + H_2O \longrightarrow CH_3NH_2 + H_3O^+\)
\(I \ \ \ \ \ \ \ \ \ \ 0.0667 \ \ \ \ \ \ \ \ \ 0\ \ \ \ \ \ \ \ \ 0\\\\C\ \ \ \ \ \ \ \ -x\ \ \ \ \ \ \ \ +x \ \ \ \ \ \ \ \ +x\\\\E \ \ \ \ \ \ \ \ \ \ \ \ 0.0667-x \ \ \ \ \ \ \ \ \ \ \ \ +x \ \ \ \ \ \ \ \ \ \ \ \+x\\\\\to Ka = \frac{[CH_3NH_2] [H_3O^+] }{[CH_3NH_3^+]}\)
Calculating \(K_a\) from \(K_b\)
\(\to K_a \times K_b = 1\times 10^{-14}\\\\\to K_a = \frac{1\times 10^{-14}}{4.4\times 10^{-4}} = 2.27\times 10^{-11}\\\\\)
\(= 2.27\times 10^{-11} \\\\= x\times \frac{x}{(0.0667-x)}\)
The x in the 0.0667-x can be ignored since the Ka value is just too small and it also does not follow the five percent criteria.
\(\to 2.27 \times 10^{-11} \times 0.0667 = x_2\\\\\to x_2 = 1.515\times 10^{-12}\\\\\to x = 1.23\times 10^{-6}\ M\\\\\to [H_3O^+] = x = 1.23\times 10^{-6}\ M\\\\\)
We have the formula to calculate pH.
\(\to pH = - \log [H_3O^+] = - \log 1.23\times 10^{-6}\ M= 5.91\)
The pH at the equivalent point for this titration is "5.91".
Find out more information about the pH here:
brainly.com/question/15289741