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Predict the major product obtained when each of the following compounds is treated with fuming sulfuric acid: (a) Chlorobenzene (b) Phenol (c) Benzaldehyde (d) Ortho-Nitrophenol (e) Para-Bromotoluene... Aspartame (below) is an artificial sweetener used in diet soft drinks and is marketed under many trade names, including Equal TM and Nutrasweet TM . In the body, aspartame is hydrolyzed to produce... Draw the enolate ion that is formed when each of the following compounds is treated with sodium ethoxide. In each case, draw all resonance structures of the enolate ion, and predict whether a... Identify the reagents that you would use to accomplish each of the following transformations (you will need to use reactions from previous chapters). (a) (b) (c) (d) OEt CI Consider the 1s np 3 P 1s nd 3 D transition in He. Draw an energy-level diagram, taking the spin-orbit coupling that splits terms into levels into account. Into how many levels does each term split?... Identify the reagents that you would use to produce each of the following compounds using a Claisen condensation. (a) (b) (c) (d) (e) OEt OEt The principal line in the emission spectrum of sodium is yellow. On close examination, the line is seen to be a doublet with wavelengths of 589.0 and 589.6 nm. Explain the source of this doublet. Use the transition frequencies shown in Example Problem 22.7 to calculate the energy (in joules and electron-volts) of the six levels relative to the 3s 2 S 1/2 level. State your answers with the... Propose an efficient synthesis for each of the following transformations. (a) (b) (c) (d) OEt EtO Predict the major product obtained when each of the following amines is treated with a mixture of NaNO 2 and HCl: (a) (b) (c) (d) NH2 Z Evaluate the energy for the two MOs generated by combining a H1s and a F2p AO. Use Equation (23.12) and carry out the calculation for S HF = 0.075, 0.18, and 0.40 to mimic the effect of increasing... Draw the structure of each of the following compounds: (a) Cyclohexylmethylamine (b) Tricyclobutylamine (c) 2,4-Diethylaniline (d) (1R,2S)-2-Methylcyclohexanamine (e) ortho-Aminobenzaldehyde Sketch the molecular orbital energy diagram for the radical OH based on what you know about the corresponding diagram for HF. How will the diagrams differ? Characterize the HOMO and LUMO as... Why are the magnitudes of the coefficients c a and c b in the H 2 + wave functions g and u equal? Meta-Bromoaniline was treated with NaNO 2 and HCl to yield a diazonium salt. Draw the product obtained when that diazonium salt is treated with each of the following reagents: (a) H 2 O (b) HBF 4 (c)... The two linearly independent total energy eigenfunctions for rotation in two dimensions are What is the evolution in time of for each of these solutions? 1 , (0) 1 e and o_(0) 2T |-4 1, The following images show contours of constant electron density for H 2 calculated using the methods described in Chapter 26. The values of electron density are (a) 0.10, (b) 0.15, (c) 0.20, (d)... Express the rate of reaction with respect to each species in the following reactions: a. 2NO(g) + O 2 (g) N 2 O 4 (g) b. H 2 (g) + I 2 (g) 2HI(g) c. ClO (g) + BrO (g) ClO 2 (g) + Br(g) The molecular electrostatic potential maps for LiH and HF are shown here. Does the apparent size of the hydrogen atom (shown as a white sphere) tell you whether it is an electron acceptor or an... Calculate the bond order in each of the following species. Which of the species in parts (a)(d) do you expect to have the shorter bond length? a. Li 2 or Li + 2 b. C 2 or C + 2 c. O 2 or O + 2 d. F 2... Electron-donating groups on benzene promote electrophilic aromatic substitution and lead preferentially to so-called ortho and para products over meta products, whereas electron-withdrawing groups... BeH 2 is linear, whereas CH 2 with two additional electrons and H 2 O with four additional electrons are both bent to a similar degree. Could these changes in geometry have been anticipated by... A tube of superglue will harden if it remains open too long in a humid environment. Draw a mechanism that shows how superglue polymerizes in the presence of atmospheric moisture. When drawing your... Kevlar is a condensation polymer used in the manufacture of bulletproof vests. Identify the monomers required for the preparation of Kevlar. Kevlar The beam is supported by two rods AB and CD that have cross-sectional areas of 12 mm 2 and 8 mm 2 , respectively. Determine the position d of the 6-kN load so that the average normal stress in each... Determine the resultant internal loadings acting on the cross section at points B and C of the curved member. A 45 2 ft 500 lb 30 The hand crank that is used in a press has the dimensions shown. Determine the resultant internal loadings acting on the cross section at point A if a vertical force of 50 lb is applied to the handle... The boom DF of the jib crane and the column DE have a uniform weight of 50 lb/ft. If the supported load is 300 lb, determine the resultant internal loadings in the crane on cross sections at points... The gas-phase decomposition of ethyl bromide is a first-order reaction, occurring with a rate constant that demonstrates the following dependence on temperature: a. Determine the Arrhenius parameters... Consider the unimolecular isomerization of methylcyanide, a reaction that will be discussed in detail in Chapter 36: CH 3 NC(g) CH 3 CN(g) The Arrhenius parameters for this reaction are A = 2.5 10... The following compound has one aldehyde group and two OH groups: Under acidic conditions, either one of the OH groups can function as a nucleophile and attack the carbonyl group, giving rise to two... The rigid beam is supported by a pin at C and an A-36 steel guy wire AB. If the wire has a diameter of 0.2 in., determine how much it stretches when a distributed load of w = 100 lb/ft acts on the... Salicin is a natural analgesic present in the bark of willow trees, and it has been used for thousands of years to treat pain and reduce fevers. (a) Is salicin a reducing sugar? (b) Identify the... How many different pentapeptides can be constructed from the 20 naturally occurring amino acids in the following table? Abbreviation Name Structure Abbreviation Name Structure Amino acids with polar... Identify the monomers required to make each of the following condensation polymers. (a) (b) Draw the monomer(s) required to make each of the following condensation polymers: (a) (b) Z Z Z Kodel is a synthetic polyester with the following structure. (a) Identify what monomers you would use to make Kodel. (b) Would you use acidic conditions or basic conditions for this polymerization... Polyformaldehyde, sold under the trade name Delrin, is a strong polymer used in the manufacture of many guitar picks. It is prepared via the acid-catalyzed polymerization of formaldehyde. (a) Draw... If the gears are subjected to the torques shown, determine the maximum shear stress in the segments AB and BC of the A-36 steel shaft. The shaft has a diameter of 40 mm. 300 N-m 100 N-m 200 N-m The metal stud punch is subjected to a force of 120 N on the handle. Determine the magnitude of the reactive force at the pin A and in the short link BC. Also, determine the resultant internal... The copper pipe has an outer diameter of 40 mm and an inner diameter of 37 mm. If it is tightly secured to the wall and three torques are applied to it, determine the absolute maximum shear stress... The assembly consists of two posts AB and CD each made from material 1 having a modulus of elasticity of E 1 and a cross-sectional area A1, and a central post EF made from material 2 having a modulus... The A-36 solid steel shaft is 2 m long and has a diameter of 60 mm. It is required to transmit 60 kW of power from the moor M to the pump P. Determine the smallest angular velocity the shaft if the... Rods AB and BC have diameters of 4 mm and 6 mm, respectively. If the 3 kN force is applied to the ring at B, determine the angle θ so that the average normal stress in each rod is... If the allowable tensile stress for wires AB and AC is Ï allow = 200 MPa, determine the required diameter of each wire if the applied load is P = 6 kN. 45 Determine the shear strain γ xy at corners D and C if the plastic distorts as shown by the dashed lines. y 12 mm 4 mm 8 mm IB 3 mm 300 mm 12 mm |A -400 mm- 5 mm The steel shaft has a diameter of 40 mm and is fixed at its ends A and B. If it is subjected to the couple, determine the maximum shear stress in regions AC and CB of the shaft. G st = 75 GPa. 3 kN A... A portion of an airplane fuselage can be approximated by the cross section shown. If the thickness of its 2014-T6-aluminum skin is 10 mm, determine the maximum wing torque T that can be applied if... The shaft is made of an elastic perfectly plastic material as shown. Plot the shear-stress distribution acting along a radial line if it is subjected to a torque of T = 20 kN m. What is the residual... Draw the shear and moment diagrams for the beam, and determine the shear and moment in the beam as functions of x for 0 ¤ x < 4 ft, 4 ft < x < 10 ft, and 10 ft < x < 14 ft. 250 Ib 250 lb 150... If the force applied to the handle of the load binder is 50 lb, determine the tensions T 1 and T 2 in each end of the chain and then draw the shear and moment diagrams for the arm ABC. 50 lb F12 in.-... Draw the shear and moment diagrams for the beam. 2 kip/ft 30 kip-ft -5 ft- -5 ft -5 ft Members ABC and BD of the counter chair are rigidly connected at B and the smooth collar at D is allowed to move freely along the vertical post. Draw the shear and moment diagrams for member ABC. -P... The beam is constructed from four pieces of wood, glued together as shown. If M = 10 kip ft, determine the maximum bending stress in the beam. Sketch a threedimensional view of the stress... The beam is made from three boards nailed together as shown. If the moment acting on the cross section is M = 600 N m, determine the resultant force the bending stress produces on the top board. 25... For the curved beam in Fig. 640a, show that when the radius of curvature approaches infinity, the curved-beam formula, Eq. 624, reduces to the flexure formula, Eq. 613. Determine the maximum allowable intensity w of the uniform distributed load that can be applied to the beam. Assume w passes through the centroid of the beams crosssectional area, and the beam is... The composite beam is made of steel (A) bonded to brass (B) and has the cross section shown. If the allowable bending stress for the steel is (Ï allow ) st = 180 MPa, and for the brass (Ï... If the applied shear force V = 18 kip, determine the maximum shear stress in the member. 3 in. 1 in. in. '1 in. 1 in. The overhang beam is subjected to the uniform distributed load having an intensity of w = 50 kN/m. Determine the maximum shear stress in the beam. B- -3 m -3 m- 50 mm 100 mm If the wide-flange beam is subjected to a shear of V = 30 kN, determine the maximum shear stress in the beam. Set w = 300 mm. 200 mm 20 mm 20 mm 300 mm 200 mm 20 mm If the wide-flange beam is subjected to a shear of V = 20 kN, determine the maximum shear stress in the beam. 200 mm 20 mm 20 mm - 300 mm 200 mm 20 mm The composite beam is made of A-36 steel (A) bonded to C83400 red brass (B) and has the cross section shown. If it is subjected to a moment of M = 6.5 kN · m, determine the maximum stress in... Determine the shear and moment in the beam as functions of x, where 0 ¤ x < 6 ft, then draw the shear and moment diagrams for the beam. 8 kip 2 kip/ft 50 kip-ft 6 ft 4 ft Determine the shape factor of the cross section. 100 mm 100 mm 100 mm 100 mm 100 mm 100 mm If the wide-flange beam is subjected to a shear of V = 30 kN, determine the maximum shear stress in the beam. Set w = 200 mm. 200 mm 30 mm 25 mm A. 250 mm 30 mm If w = 800 lb/ft, determine the absolute maximum shear stress in the beam. The supports at A and B are smooth. 3 ft - 3 ft 6 ft The beam is subjected to a shear force of V = 50 kip. Determine the shear flow at points A and B. 1 in. 5 in. 1 in. 5 in. 9 in. 1 in. B 12 in. The simply supported beam is built up from three boards by nailing them together as shown. The wood has an allowable shear stress of Ï allow = 1.5 MPa, and an allowable bending stress of Ï... A spherical gas tank has an inner radius of r = 1.5 m. If it is subjected to an internal pressure of p = 300 kPa, determine its required thickness if the maximum normal stress is not to exceed 12 MPa. Determine the location e of the shear center, point O, for the tube having a slit along its length. The inner ring A has an inner radius r 1 and outer radius r 2 . The outer ring B has an inner radius r 3 and an outer radius r 4 , and r 2 > r 3 . If the outer ring is heated and then fitted over the... A pressure-vessel head is fabricated by welding the circular plate to the end of the vessel as shown. If the vessel sustains an internal pressure of 450 kPa, determine the average shear stress in the... The built-up beam is formed by welding together the thin plates of thickness 5 mm. Determine the location of the shear center O. -5 mm 200'mm 100 mm 100 mm 200 mm 300 mm A boiler is constructed of 8-mm-thick steel plates that are fastened together at their ends using a butt joint consisting of two 8-mm cover plates and rivets having a diameter of 10 mm and spaced 50... Air pressure in the cylinder is increased by exerting forces P = 2 kN on the two pistons, each having a radius of 45 mm. If the cylinder has a wall thickness of 2 mm, determine the state of stress in... The 20-kg drum is suspended from the hook mounted on the wooden frame. Determine the state of stress at point E on the cross section of the frame at section aa. Indicate the results on an element. 50... Determine the stress components acting on the inclined plane AB. Solve the problem using the method of equilibrium described in Sec. 9.1. 8 ksi 5 ksi 40 3 ksi The post has a circular cross section of radius c. Determine the maximum radius e at which the load P can be applied so that no part of the post experiences a tensile stress. Neglect the weight of... Sketch the normal-stress distribution acting over the cross section at section aa. Neglect the weight of the block. 6 kip -3 in. 12 kip 6 in. D. B. The rod has a diameter of 40 mm. If it is subjected to the force system shown, determine the stress components that act at point A, and show the results on a volume element located at this point. 100... The block is subjected to the eccentric load shown. Sketch the normal-stress distribution acting over the cross section at section aa. Neglect the weight of the block. 100 mm 150 kN 150 mm Determine the equivalent state of stress on an element at the same point which represents (a) the principal stress, and (b) the maximum in-plane shear stress and the associated average normal stress.... The internal loadings at a cross section through the 6-in. diameter drive shaft of a turbine consist of an axial force of 2500 lb, a bending moment of 800 lb · ft, and a torsional moment of... The internal loadings at a cross section through the 6-in. diameter drive shaft of a turbine consist of an axial force of 2500 lb, a bending moment of 800 lb · ft, and a torsional moment of... Determine the principal stresses, the maximum in-plane shear stress, and average normal stress. Specify the orientation of the element in each case. 20 MPa 80 MPa 30 MPa The grains of wood in the board make an angle of 20° with the horizontal as shown. Determine the normal and shear stresses that act perpendicular and parallel to the grains if the board is... The pedal crank for a bicycle has the cross section shown. If it is fixed to the gear at B and does not rotate while subjected to a force of 75 lb, determine the principal stresses on the cross... The solid shaft is subjected to a torque, bending moment, and shear force. Determine the principal stresses at points A and B and the absolute maximum shear stress. 450 mm 300 N-m 25 mm 45 N-m 800 N Solve Prob. 10â¬3 for an element oriented ø = 30ð clockwise. A closed storage building is located on open flat terrain in central Ohio. If the side wall of the building is 20 ft high, determine the external wind pressure acting on the windward and leeward... Determine the reactions on the beam. 3 k/ft 2 k/ft 2 k/ft |B, 60 600 k ft 12 ft 12 ft Determine the reactions at the smooth support C and pinned support A. Assume the connection at B is fixed connected. 80 lb/ft 30 10 ft -6 ft- Classify each of the structures as statically determinate, statically indeterminate, stable, or unstable. If indeterminate, specify the degree of indeterminacy. The supports or connections are to be... Determine the reactions at the supports A and B. 700 lb/ft 20 ft 500 lb/ft B 30 ft 48 ft- 48 ft- Classify each of the structures as statically determinate, statically indeterminate, or unstable. If indeterminate, specify the degree of indeterminacy. a. b. c. Classify each of the structures as statically determinate, statically indeterminate, or unstable. If indeterminate, specify the degree of indeterminacy. a. b. c. d. Classify each of the following trusses as statically determinate, statically indeterminate, or unstable. If indeterminate, state its degree. a. b. c. d. Determine the force in each member of the space truss and state if the members are in tension or compression. -2 m E Do 5 m 3 m -y 4 m. 6 kN Determine the force in each member of the space truss and state if the members are in tension or compression. The truss is supported by ball-and socket joints at C, D, E, and G. Although this truss...
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