Answer:
[tex]D=0.016m[/tex]
Explanation:
From the question we are told that:
Discharge Rate [tex]F_r=0.5kgls[/tex]
Pressure [tex]P=15Kpa[/tex]
Temperature [tex]T=25=>298K[/tex]
Ambient pressure is 1 atm.
Generally the equation for Density is mathematically given by
[tex]\rho=\frac{PM}{RT}[/tex]
[tex]\rho=\frac{15*10^5*28.0134*10^{-3}}{8.314*298}[/tex]
[tex]\rho=16.958kg/m^2[/tex]
Generally the equation for Flow rate is mathematically given by
[tex]F_r=\mu A\sqrt{Q \rho P(\frac{2}{Q+1})^{\frac{Q+1}{Q-1}}}[/tex]
Where
[tex]Q=Heat coefficient\ ratio\ of\ Nitrogen[/tex]
[tex]Q=1.4[/tex]
[tex]\mu= Discharge\ coefficient[/tex]
[tex]\mu=0.68[/tex]
Therefore
[tex]0.5=0.68 A\sqrt{1.4 16.958 15*10^{5}(\frac{2}{1.4+1})^{\frac{1.4+1}{1.4-1}}}[/tex]
[tex]A=2.129*10^{-4}[/tex]
Where
[tex]A=\frac{\pi}{4}D^2[/tex]
[tex]\frac{\pi}{4}D^2=2.129*10^{-4}[/tex]
[tex]D=0.016m[/tex]
EnQueue(X): Thêm phần tử X vào Queue
DeQueue() : Lấy 1 phần tử ra khỏi Queue
Hãy cho biết phần tử ở đầu của Queue có giá trị bằng bao nhiêu sau khi thực hiện lần lượt các phép toán sau:
EnQueue(1); EnQueue(2); DeQueue(); EnQueue(3);
EnQueue(4); DeQueue(); DeQueue();
Transients (surges) on a line can cause spikes or surges of energy that can damage delicate electronic components. A SPD device contains one or more ________________ than bypass and absorb the energy of the transient.
Answer:
I think ( MOV Metal oxide varistors )
Transients (surges) on a line can cause spikes or surges of energy that can damage delicate electronic components. A SPD device contains one or more MOV Metal oxide varistors than bypass and absorb the energy of the transient.
An unconstrained 10mm thick plate of steel 100mm on a side with a 25mm diameter hole in the center is heated from 20 degrees C to 120 degrees C. The linear CTE is 12x10-6/⁰C. What is the final diameter of the hole
Answer:
The correct answer is "25.03 mm".
Explanation:
Given:
Thickness of plate,
= 10 mm
On a side,
= 100 mm
Diameter hole,
= 25 mm
Coefficient of thermal expansion,
CTE = [tex]12\times 10^{-6} /^{\circ} C[/tex]
Now,
⇒ [tex]D_i\times (12\times 10^{-6}) \Delta \theta = \Delta D[/tex]
= [tex]25\times 12\times 10^{-6} \Delta \theta[/tex]
= [tex]3\times 10^{-4} \Delta \theta[/tex]
= [tex]3\times 10^{-2}[/tex]
hence,
The final diameter of hole will be:
[tex]D_f=25.03 \ mm[/tex]
The maximum tensile force a solid, cylindrical wire can withstand increases as the thickness of the wire increases.
True
False
Explain ROLAP, and list the reasons you would recommend its use in the relational database environment.
Answer:
ROLAP is a branch of OLAP that is used to contain Relational database ( RDB ). which is a very fast database ( quick process of queries )
Very fast to access and also fast in processing queries provides multidimensional view of data / supports multidimensional database schema with RDBMssupports large databasesExplanation:
ROLAP ( Relational On-line Analytical processing ) is a branch of OLAP that is used to contain Relational database ( RDB ).
Advantages of ROLAP ( reasons for the use of ROLAP )
Very fast to access ( fast in processing queries )provides multidimensional view of data / supports multidimensional database schema with RDBMssupports large databasesa video inspection snake is use
Answer:
very good thx
Explanation:
Wave flow of an incompressible fluid into a solid surface follows a sinusoidal pattern. Flow is two-dimensional with the x-axis normal to the surface and y axis along the wall. The x component of the flow follows the pattern
u = Ax sin (2πt/T)
Determine the y-component of flow (v) and the convective and local components of the acceleration vector.
Answer:
sorry , for my point
Explanation:
What are the assumptions made for air standard cycle analysis?
a.The working medium is prefect gas throughout i.e. it follows PV=mRT
b.The working medium does not undergo any chemical change throughout the cycle
c.The compression and expansion processes are reversible adiabatic i.e. there is no loss or gain in entropy.
d.All of above
Block A hangs by a cord from spring balance D and is submerged in a liquid C contained in beaker B. The mass of the beaker is 1.20 kg; the mass of the liquid is 1.85 kg. Balance D reads 3.10 kg and balance E reads 7.50 kg. The volume of block A is 4.15 × 10−3 m3.
a) What is the density of the liquid?
b) What will the balance D read if block A is pulled up out of the liquid?
c) What will the balance E read if block A is pulled up out of the liquid?
Answer:
a) [tex]m_e= 3.05 Kg[/tex]
b) [tex]\rho=1072.3kg/m^3[/tex]
c) [tex]m_e= 3.05 Kg[/tex]
Explanation:
From the question we are told that:
Beaker Mass [tex]m_b=1.20[/tex]
Liquid Mass [tex]m_l=1.85[/tex]
Balance D:
Mass [tex]m_d=3.10[/tex]
Balance E:
Mass [tex]m_e=7.50[/tex]
Volume [tex]v=4.15*10^{-3}m^3[/tex]
a)
Generally the equation for Liquid's density is mathematically given by
[tex]m_e=m_b+m_l+(\rho*v)[/tex]
[tex]\rho=\frac{7.50-(1.2+1.85)}{4.15*10^{-3}}[/tex]
[tex]\rho=1072.3kg/m^3[/tex]
b)
Generally the equation for D's Reading at A pulled is mathematically given by
m_d = mass of block - mass of liquid displaced
[tex]m_d=m- (\rho *v )[/tex]
[tex]m=3.10+ (1072.30 *4.15*10^{-3}m^3 )[/tex]
[tex]m=18.10kg[/tex]
c)
Generally the equation for E's Reading at A pulled is mathematically given by
[tex]m_e=m_b+m_l[/tex]
[tex]m_e = 1.20 + 1.85[/tex]
[tex]m_e= 3.05 Kg[/tex]
Which of the following would make a column more likely to buckle?
Increase its ultimate compressive strength
Increase its length
Increase its Young’s modulus
Increase its cross-sectional area
Increase its area moment of inertia
True or false: Increasing a material’s ultimate compressive strength makes it less likely to crush under its own weight (assuming all other things equal).
True
False
True or false: The area moment of inertia of an object only depends on its shape, not its size.
True
False
Answer:
1) B: Increase its length
2) True
3) True
Explanation:
1) Columns are compressive members and are subjected to primarily compressive stresses.
Now, there is what we call slender Ness ratio in columns which is basically used to check the ability of a column to resist buckling.
The formula is;
Slenderness ratio = Effective length of column/radius of gyration
Thus, the longer the column the more the Slenderness ratio and the more likely it is to buckle.
Thus, increasing the length is what makes columns likely buckle.
2) Compressive strength is the ability of a material to withstand loads that may reduce size or make the material crush under load.
Now, increasing the compressive strength simply means more ability to withstand loads that may lead to crushing under load.
Ultimate compressive strength is the maximum amount of compressive stress that a material can take before it crushes under load. Thus, increasing the ultimate compressive strength means it is less likely to crush under its own weight.
3) There are different factors that affect moment of inertia and they are;
- the mass of the body
- axis of rotation of the body
- shape and size of the body.
However, for area moment of inertia, what is most relevant to us is the shape of the body in question since we are dealing with area and not how big it is.
A investor will invest in mutual fundwith a probability of 0.6, will invest in government fundwith a probability of 0.3, and will invest in both fundswith a probability of 0.15. Find the probability that the investor will invest in either mutual fundor government fund.
Answer:
0.75
Explanation:
From this question above we have the following information
A = probability of investment in mutual fund= 0.6
B = probability of investment in government fund = 0.3
C = probability of investing in both the mutual fund and the government= 0.15
Where to find the probability of this investor investing in either of these two
= Prob(a) + prob(b) - prob(c)
= 0.6 + 0.3 - 0.15
= 0.9 - 0.15
= 0.75
Alternating current lesson 4 exam
If a cylindrical part with a length of 20 mm and a diameter of 20 mm is to be machined to a cylindrical part with 18 mm in diameter with the same length. The machine has a mechanical efficiency of 50% and a power of 80 kW. If the cutting rake angle is 0 degrees and the cutting tool is made of uncoated carbides and the cutting speed is 10 m/s. What material can we choose for the cylinder
Answer:
Titanium Alloy
Explanation:
Length ( L ) = 20 mm
D1 = 20 mm
d2 = 18 mm
l = 20 mm
Mechanical efficiency = 50%
power = 80 kW
cutting rake angle = 0°
cutting speed ( v ) = 10 m/s
Determine the material to be for the cylinder
In order to choose a material for the cylinder we have to calculate the cutting force
P = Fc * V
80 = Fc * 10 m/s
therefore Fc = 80 / 10 = 8 N
Hence the material we can use is Titanium Alloy due to low cutting force value
Given : x² + 200x = 166400 The current park is a square, and the addition will increase the width by 200 meters to give the expanded park a total area of 166,400 square meters To Find : the side length of the current square park. Solution: x² + 200x = 166400 => x(x + 200) = 166400 166400 = 320 * 520 => (320)(320 + 200) = 166400 => x = 320 side length of the current square park. = 320 m Learn More: Which expression is a possible leading term for the polynomial ... brainly.In/question/13233517
Answer:
320 m
Explanation:
To find the side length of the current park, x, we solve the quadratic equation for the area of the park
x² + 200x = 166400
x² + 200x - 166400 = 0
We multiply -166400 by x² to get -166400x². We now find the factors of 166400x² that will add up to 200x. These factors are -320x and 520x
So, we re-write the expression as
x² + 200x - 166400 = 0
x² + 520x - 320x - 166400 = 0
We write out the factors of the expression,
x² + 520x - 320x - 320 × 520 = 0
Factorizing the expression, we have
x(x + 520) - 320(x + 520) = 0
(x + 520)(x - 320) = 0
x + 520 = 0 or x - 320 = 0
x = -520 or x = 320
Since x is not negative, we take the positive answer.
So, x = 320 m
A gas tank is known to have a thickness of 0.5 inches and an internal pressure of 2.2 ksi. Assuming that the maximum allowable shear stress in the tank wall is 12 ksi, determine the necessary outer diameter for the tank. Assume that the tank is made of a cold drawn steel whose elastic modulus is 35000 ksi and whose Poisson ratio is 0.292. If y
Answer:
[tex]D_o=11.9inch[/tex]
Explanation:
From the question we are told that:
Thickness [tex]T=0.5[/tex]
Internal Pressure[tex]P=2.2Ksi[/tex]
Shear stress [tex]\sigma=12ksi[/tex]
Elastic modulus [tex]\gamma= 35000[/tex]
Generally the equation for shear stress is mathematically given by
[tex]\sigma=\frac{P*r_1}{2*t}[/tex]
Where
r_i=internal Radius
Therefore
[tex]12=\frac{2.2*r_1}{2*0.5}[/tex]
[tex]r_i=5.45[/tex]
Generally
[tex]r_o=r_1+t[/tex]
[tex]r_o=5.45+0.5[/tex]
[tex]r_o=5.95[/tex]
Generally the equation for outer diameter is mathematically given by
[tex]D_o=2r_o[/tex]
[tex]D_o=11.9inch[/tex]
Therefore
Assuming that the thin cylinder is subjected to integral Pressure
Outer Diameter is
[tex]D_o=11.9inch[/tex]
A force measuring instrument comes with a certificate of calibration that identifies two instrument errors and assigns each an uncertainty at 95% confidence over its range. Provide an estimate of the instrument design-stage uncertainty.
Resolution: 0.25 N
Range: 0 to 100 N
Linearity error: within 0.20 N over range
Hysteresis error: within 0.30 N over range
Answer:
[tex]U=\pm 0.382N[/tex]
Explanation:
From the question we are told that:
Resolution: 0.25 N
Range: 0 to 100 N
Linearity error: within 0.20 N over range
Hysteresis error: within 0.30 N over range
Generally the equation for Stage Uncertainty is mathematically given by
[tex]U=\sqrt{u_0^2+u_T^2}[/tex]
Where
[tex]u_0=Zero\ order\ uncertainty[/tex]
[tex]u_0=\pm 0.5*0.25[/tex]
[tex]u_0=\pm=0.125[/tex]
And
u_T=Total instrumental Uncertainty
[tex]u_T=\sqrt{l_e^2+h_e^2}[/tex]
Where
l_e=Error of linearity
h_e=Error due to hysteresis
Hence
[tex]u_T=\sqrt{0.20^2+0.30^2}[/tex]
[tex]u_T=\pm 0.36[/tex]
Therefore
[tex]U=\sqrt{(0.125)^2+0.36^2}[/tex]
[tex]U=\pm 0.382N[/tex]
Tech A says that proper footwear may include both leather and steel-toed shoes. Tech B says that when working in the shop, you only need to wear safety glasses if you are doing something dangerous. Who is correct?
Answer:
Tech A is correct.
Explanation:
If a person is doing something dangerous in a shop, he should wear safety glasses to protect his eyes from danger and also wear leather shoes to protect himself from any electric shock. Leather boots will disconnect a person with direct earth and therefore he can save himself if he gets a electric shock.
A pinion and gear pair is used to transmit a power of 5000 W. The teeth numbers of pinion
and gear are 20 and 50. The module is 5 mm, the pressure angle is 20o
and the face width is 45 mm. The
rotational speed of pinion is 300 rev/min. Both the pinion and the gear material are Nitralloy 135 Grade2 with a hardness of 277 Brinell. The quality standard number Qv is 5 and installation is open gearing
quality. Find the AGMA bending and contact stresses and the corresponding factors of safety for a
pinion life of 109
cycles and a reliability of 0.98
Answer:
mark me as a brainleast
Explanation:
209781
Karl and Susan have agreed to come to our party, _______ has made Maria very happy. that which what who
Answer:
that
I am not sure that this is the answer
but i hopethis will help you
Karl and Susan agreed to come to our party, which made Maria very happy. The correct option is b.
What are relative pronouns?Relative pronouns are words that are used to show the relation between two statements. Who/whom, whoever/whomever, whose, that, and which are the most common relative pronouns. "what," "when," and "where" might operate as relative pronouns.
Relative pronouns introduce dependent sentences called relative clauses. Happy is an emotion that is non-living things and with non-living things, which is used.
The relative pronouns "which" and "that" begin adjective clauses. Both provide additional information about the noun they follow.
Therefore, the correct option is b, which. Karl and Susan agreed to come to our party, which made Maria very happy.
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If an elevator repairer observes that cables begin to fray after 15 years, what process might he or she use to create a maintenance schedule for their replacement? fallacious reasoning reductive reasoning inductive reasoning deductive reasoning
Answer:
inductive reasoning
Explanation:
Inductive reasoning is one of the type of reasoning method in which generalized consequences are derived from limited observations. By observing few data, general conclusions are drawn. The conclusions drawn are false in inductive reasoning. In the given situation, the conclusion drawn by the elevator repairer has been drawn by inductive reasoning. His observation of some cables led him to draw the conclusion about all the cables. The result of the reasoning is false.
Two engineers are to solve an actual heat transfer problem in a manufacturing facility. Engineer A makes the necessary simplifying assumptions and solves the problem analytically, while engineer B solves it numerically using a powerful software package. Engineer A claims he solved the problem exactly and, thus, his results are better, while engineer B claims that he used a more realistic model and, thus, his results are better. Will the experiments prove engineer B right
Answer:
Engineer A results will be more accurate
Explanation:
Analytical method is better than numerical method. Engineer A has used analytical method and therefore his results will be more accurate because he used simplified method. Engineer B has used software to solve the problem related to heat transfer his results will be approximate.
Elliptic curve cryptography is considered as the latest and probably the one with a future. Having seen RSA in earlier modules, in which ways do YOU think elliptic cryptography is more advanced than RSA. You may read other material or get this information from the internet to answer this question. But make sure to provide necessary references when you do cite others.
Answer:
The answer is below.
Explanation:
Some of the ways, how I think elliptic cryptography is more advanced than RSA are the following:
1. ECC - Elliptic Curve Cryptography uses smaller keys for the same level of security, particularly at greater levels of security.
2. ECC can work well and at a faster rate on a small-capacity device compared to RSA
3. It uses offer speedier SSL handshakes that enhance security
4. It offers fast signatures
5. It allows signatures to be computed in two stages, which enables lower latency than inverse throughput.
6. Relatively quick encryption and decryption
A piece of coaxial cable has 75ohms Characteristics impedance and a nominal capacitance of 69pF/m. what is its inductance per meter ? If the diameter of the inner conductor is 0.584mm, and the dielectric constant of the insulation is 2.23, what is the outer diameter of the conductor ?
Answer:
A) L = 0.388 μm
B) D = 3.78 mm
Explanation:
We are given;
Characteristics impedance; Z_o = 75 ohms
Nominal capacitance; C = 69pF/m = 69 × 10^(-12) F/m
dielectric constant; k = 2.23
Inner diameter of conductor; d = 0.584 mm
A) Now formula for Characteristics impedance is given as;
Z_o = √(L/C)
Where L is the inductance per metre.
Making L the subject, we have;
L = (Z_o)²C
L = 75² × 69 × 10^(-12)
L = 0.388 × 10^(-6) m
L = 0.388 μm
B) To get the outer diameter, we will use the formula;
Z_o = (138/√k) log(D/d)
Where;
D is outer diameter.
Thus, Plugging in the relevant values;
75 = (138/√2.23) × log (D/0.584)
log (D/0.584) = 0.81158611538
(D/0.584) = 10^(0.81158611538)
D/0.584 = 6.48016576435
D = 6.48016576435 × 0.584
D = 3.78 mm
Please help me:
Use the Node analysis to find the power of all resistors
c. Assuming a fixed-priority scheduling. Consider two tasks to be executed periodically on a single processor, where task 1 has period p= 4 and task 2 has period p= 6.
If execution time of task I be e;=1
Find the maximum value for the execution time e2 of task 2 such that the Rate Monotonic (RM) schedule is feasible.
Answer:
hi hello tata byebye nice
As per the given data, the maximum value of e2 such that the RM schedule is feasible is 0.985.
What is fixed-priority scheduling?Fixed-priority scheduling is a scheduling algorithm used in real-time operating systems to assign priorities to tasks based on their relative importance or urgency.
In a fixed-priority scheduling algorithm, tasks with higher priority are assigned shorter periods.
Since task 1 has a period of 4 and task 2 has a period of 6, we can assume that task 1 has a higher priority than task 2. Therefore, we can apply the Rate Monotonic (RM) scheduling algorithm.
The RM scheduling algorithm states that a feasible schedule exists if the following condition is satisfied:
Σ (ei / pi) ≤ n(2^(1/n)-1)
Where Σ (ei / pi) is the sum of the ratio of execution time to period for all tasks, n is the total number of tasks, and the base of the exponential function is 2.
In this case, we have two tasks, so n = 2. We know that e1 = 1 and p1 = 4. For task 2, we need to find the maximum value of e2 such that the schedule is feasible. Therefore, we can set e2 = x and p2 = 6.
Substituting the values into the RM scheduling formula, we get
(e1/p1) + (e2/p2) ≤ 2^(1/2) - 1
(1/4) + (x/6) ≤ 0.4142
Multiplying both sides by 12, we get:
3 + 2x ≤ 4.97
2x ≤ 1.97
x ≤ 0.985
Therefore, the maximum value of e2 such that the RM schedule is feasible is 0.985.
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An ideal gas within a piston-cylinder assembly undergoes a Carnot refrigeration cycle. The isothermal compression occurs at 325 K from 2 bar to 4 bar. The isothermal expansion occurs at 250 K. Determine:
a. the coefficient of performance
b. the heat transfer to the gas during the isothermal expansion, in kj per kmol of gas
c. the magintude of the net work input, in kj per kmol of gas.
Answer:
a) [tex]\mu=3.3[/tex]
b) [tex]Q=1440.7KJ/Kmol[/tex]
c) [tex]W=1872.9KJ/Kmol[/tex]
Explanation:
From the question we are told that:
Initial Temperature [tex]T_1=325k[/tex]
initial Pressure [tex]P_1=2 bar[/tex]
Final Pressure [tex]P_2=4 bar[/tex]
iso-thermal expansion [tex]T_2=250k[/tex]
a)
Generally the equation for Coefficient of performance is mathematically given by
[tex]\mu=\frac{T_2}{T_1-T_2}[/tex]
[tex]\mu=\frac{250}{325-250}[/tex]
[tex]\mu=3.3[/tex]
b)
Generally the equation for Heat Expansion is mathematically given by
[tex]Q=RT_2 In(\frac{P_2}{P_1})[/tex]
Where
R=Gas constant
[tex]R=8.314462618[/tex]
Therefore
[tex]Q=8.314462618*250 In(\frac{4}{2})[/tex]
[tex]Q=1440.7KJ/Kmol[/tex]
c)
Generally the equation for work input is mathematically given by
[tex]W=RT_1 In(\frac{P_2}{P_1})[/tex]
[tex]W=8.314462618*250 In(\frac{4}{2})[/tex]
[tex]W=1872.9KJ/Kmol[/tex]
The coefficient of performance is 3.33, the heat transfer in the isothermal expansion is 1440.71kJ/K.mol and the work input is calculated as 1872.92kJ/K.mol
Given Data:
T1 = 325KP1 = 2 barP2 = 4 barT2 = 250KIsothermal expansion occurs at 250K.
a) The coefficient of performanceThis is calculated as
COP =[tex]\frac{T_2}{T_1-T_2}=\frac{250}{325-250} =3.33[/tex]
b) Heat Transfer in isothermal expansion[tex]Q = RT_2In(\frac{p_2}{p_1})[/tex]
Therefore; In isothermal process du = 0
R = 8.314 AkJ/K.mol
Q = 8.314 * 250 In(4/2)
Q = 1440.71kJ/K.mol
c) Work InputW[tex]_i_n[/tex]=[tex]RT_1In(\frac{p_2}{p_1})\\W_i_n=8.314*325In(4/2)\\W_i_n=1872.92kJ/K.mol[/tex]
The work input is 1872.92kJ/K.mol
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Apart from the type of emergency, what factors affect the decision on weather to evacuate or shelter in place?
Answer:
. 1. Type of building
2. Location of emergency
3. Extent of emergency
Explanation:
1. The kind of building in which people find themselves could be a factor that can be used to make this decision. a lot of buildings can be easily affected by disasters such as explosions or tornadoes the extent of the effect is dependent on how the building is constructed. in some situations it is better to shelter in, while in others it is best to evacuate.
2. Another factor to be considered is the location or area where this is happening it is good to consider this so that people can be safely moved given that help can be easily accessed or if best to stay in.
3. The last is the extent of what is happening. The risk involved is one way of making the choice to evacuate or to stay.
The factors that affect the decision on whether to evacuate or shelter in place include:
Type of building.Location of emergency.Extent of emergencyIt should be noted that the building where an individual lives play a vital role during emergencies. Buildings that have poor foundations can easily be affected during emergencies.
Another factor that should be considered is the location where the emergency is taking place. Lastly, the extent of the emergency can determine if the person should stay or not.
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In heavy traffic areas you should wave pedestrians across the street if there is no crosswalk
In heavy traffic areas, you should wave pedestrians across the street if there is no crosswalk: False.
What is a crosswalk?A crosswalk can be defined as the marked or specially paved part of a road that is characterized by heavy traffic, so as to enable pedestrians have right of way to cross the street because drivers are required by traffic law to stop for them.
However, a driver or other road users in heavy traffic areas shouldn't wave pedestrians across the street if there is no crosswalk
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How would you describe what would happen to methane if the primary bonds were to break?
Answer:
All the bonds in methane (CH4CH4) are equivalent, and all have the same dissociation energy.
The product of the dissociation is methyl radical (CH3CH3). All the bonds in methyl radical are equivalent, and all have the same dissociation energy.
The product of that dissociation is methylene (CH2CH2). All the bonds in methylene are equivalent, and all have the same dissociation energy.
The product of that dissociation is methyne (CHCH) .
The C-H bonds in methane do not have the same dissociation energy as C-H bonds in methyl radical, which in turn do not have the same dissociation energy as the C-H bonds in methylene, which are again different from the C-H bond in methyne.
If (by some miracle) you were able to get all four bonds in methane to dissociate absolutely simultaneously, they would all show the same dissociation energy… but that energy, per bond broken, would be different than the energy required to break just one C-H bond in methane, because the products are different.
(In this case, it’s CH4→C+4HCH4→C+4H versus CH4→CH3+HCH4→CH3+H.)
To alter hydrocarbons you add enough energy to break a C-H bond. Why does only one bond break? What concentrates the energy on one C-H bond?
the weakest CH bond is the one that breaks. in plain alkanes it has to do with the molecular orbital interactions between neighboring carbon atoms. look at propane for example. the middle carbon has two C-C bonds, and each of those C-C bonds is strengthened by slight electron delocalization from the C-H bonds overlapping with the antibonding orbitals of the adjacent carbons.
since the C-H bonds on the middle carbon donate electron density to both of its neighbors, those two are weakest.
one of them will break preferentially.
which one actually breaks depends on the reaction conditions (kinetics). frankly it's whichever one ramdomly approaches a nucleophile first. when the nucleophile pulls of one of the H's, the other C-H bonds start to share (delocalize) the negative charge across the whole molecule. so while the middle C feels the majority of the negative charge character, the other two C's take on a fair amount as well...
by the way, alkanes don't really like to break and form anions like that.
a better example would be something like isopropyl iodide, where the C-I bond breaks and the I carries away the electron pair, forming a carbocation (also not particularly stable, but more so than the carbanion).
Doubling the diameter of a solid, cylindrical wire doubles its strength in tension.
True
False
Answer:
True ❤️
-Solid by solid can make Cylindrical wire doubles Strengths in tension
