FREE Trial S
study help categories /Sciences

Top Selling Sciences Questions

Formulate a mechanism for the reaction of butanedioic (succinic) anhydride with methanol shown on p. 935. Data From Problem 935 CH,OH H; + Alcoholysis (ester formation) 83% Propanoic anhydride... For each of the naturally occurring lactones below, draw the structure of the compound that would result from hydrolysis using aqueous base. (a) (b) (c) Sedanenolide, major contributor to the flavor... Give the products of reaction of -valerolactone (5-methyloxa-2-cyclopentanone,) with each of the reagents in Problem 39. Data From Problem 39 (a) NaOH, H 2 O, heat; then H + , H 2 O (b) (CH 3 ) 2... A common application of the Cope rearrangement is in ring-enlargement sequences. Fill in the reagents and products missing from the following scheme, which illustrates the construction of a... A fluid of unknown density is used in two manometersone sealed-end, the other across an orifice in a water pipeline. The readings shown here are obtained on a day when barometric pressure is 756 mm... Using the methods described in this chapter, design a multistep synthesis of each of the following molecules, making use of the indicated building blocks as the sources of all the carbon atoms in... A compound with m.p. = -22C has a parent peak in its mass spectrum at m/z = 113. The 1 H NMR spectrum shows absorptions at = 1.2 (t, 3 H), 3.5 (s, 2 H), and 4.2 (q, 2 H). The IR spectrum exhibits... Which of the following compounds would you expect to be the major organic product of the two-step sequence shown here? (a) (b) (c) (d) H3 THF CH,CHI + (CH;CH),NLi An artificial kidney is a device that removes water and waste metabolites from blood. In one such device, the hollow fiber hemodialyzer, blood flows from an artery through the insides of a bundle of... In the production of a bean oil, beans containing 13.0 wt% oil and 87.0% solids are ground and fed to a stirred tank (the extractor) along with a recycled stream of liquid n-hexane. The feed ratio is... Methanol is formed from carbon monoxide and hydrogen in the gas-phase reaction The mole fractions of the reactive species at equilibrium satisfy the relation where P is the total pressure (atm), Ke... The quantity of sulfuric acid used globally places it among the most plentiful of all commodity chemicals. In the modern chemical industry, synthesis of most sulfuric acid utilizes elemental sulfur... Iron in the form of fine wire burns in oxygen to form iron(III) oxide. 4Fe(s) + 3O 2 (g) 2Fe 2 O 3 (s) How many moles of O 2 are needed to produce 7.38 mol Fe 2 O 3 ? You are performing an experiment to measure the specific internal energy of a gas relative to a reference state of 25C and 1 atm (at which conditions U is arbitrarily set equal to 0). The gas is... Liquid water is fed to a boiler at 24C and 10 bar and is converted at constant pressure to saturated steam. (a) Use the steam tables to calculate H(kJ/kg) for this process, and then determine the... Water is to be pumped from a lake to a ranger station on the side of a mountain (see figure). The length of pipe immersed in the lake is negligible compared to the length from the lake surface to the... Calculate H for each of the following processes. In each case, restate your result as a specific enthalpy relative to a reference state. [The solutionwhich you should verifyand the restatement for... The flow of groundwater often plagues construction of tunnels and other underground systems. One way of preventing it is with an ice sealfreezing the water in the soil so that the ice formed is a... Pure ethane is burned completely with preheated 20% excess air. The combustion product gas passes through an insulated heat exchanger (the preheater) in which it transfers heat to the air that will... Sixty-five liters of liquid ethanol at 70.0C and 55 L of liquid water at 20.0C are to be mixed in a wellinsulated flask. The energy balance for this constant pressure process is Q = H. (a) Neglecting... Is it possible to precipitate 99.0% of 0.010 M Ce 3 + by adding oxalate (C 2 O 2 4 - ) without precipitating 0.010 M Ca 2 + ? CaC 2 O 4 Ksp = 1.3 10 -8 Ce 2 (C 2 O 4 ) 3 Ksp = 5.9 10 -30 Complete and balance the nuclear equations for the following fission or fusion reactions: (a) (b) H + H3He Consider a binomial experiment with n = 10 and p = .10. a. Compute f (0). b. Compute f (2). c. Compute P(x 2). d. Compute P(x 1). e. Compute E(x). f. Compute Var(x) and s. a. Which of the following reaction mixtures ill produce hydrogen more quickly at room temperature? (i) Zinc granules + dilute nitric acid (ii) Zinc powder + dilute nitric acid b. Give an explanation... Tell whether the compounds of each pair are enantiomers, diastereomers, constitutional isomers, or not isomeric. a. b. c. d. CHO H- -OH HO- HO and H- H- HO- HO- H,OH H2OH Listed below are four compounds that have the molecular formula C 6 H 6 . Which of these compounds would yield only one monosubstitution product, if, for example, one hydrogen were replaced by... Copy and complete the table shown below: measurement unit symbol length kilogram ? (a) When n-heptane burns in a gasoline engine, the combustion process takes place too quickly. The explosive detonation makes a noise called knocking. When 2,2,4-trimethylpentane (isooctane) is... Calcium oxide reacts with hydrochloric acid according to the equation: CaO + 2HCl CaCl 2 + H 2 O a. What mass of calcium chloride is formed when 28.05 g of calcium oxide reacts with excess... a. Define the following: i. 1st ionisation energy. ii. 3rd ionisation energy. b. Give the equations representing: i. The 1st ionisation energy of magnesium ii. The 3rd ionisation energy of magnesium.... a. The first six ionisation energies of an element are 1090, 2350, 4610, 6220, 37800 and 47300 kJ mol 1 . Which group in the Periodic Table does this element belong to? Explain your decision. b. Draw... (a) Hydrogen peroxide (HOOH) has a pK a of 11.6, making it roughly 10,000 times as strong an acid as water (pK a = 15.7). Explain why H 2 O 2 is a stronger acid than H 2 O. (b) In contrast to part... Draw dot-and-cross diagrams for the following covalently bonded molecules; show only the outer electron shells: a. Ethene, CH 2 CH 2 b. Carbon disulfide, CS 2 . Show how you would use Robinson annulations to synthesize the following compounds. Work backward, remembering that the cyclohexenone is the new ring and that the double bond of the cyclohexenone is... Show how you would accomplish the following multistep conversions. You may use any additional reagents you need. a. b. c. d. dimethyl adipate and allyl bromide The solubility of a salt in water depends on a broad range of intermolecular bonding forces. These occur between the particles or ions making up the salt, between the salts particles and solvating... Refer to the periodic table (Figure 2.15 or inside front cover) and obtain the group and period for each of the following elements. Also determine whether the element is a metal, nonmetal, or... A stone is thrown horizontally from the top of a vertical cliff and lands 4.0 s later at a distance 12.0 m from the base of the cliff. Ignore air resistance. a. Calculate the horizontal speed of the... Trials on the surface of a new road show that, when a car skids to a halt, its acceleration is 7.0 m s 2 . Estimate the skid-to-stop distance of a car travelling at a speed limit of 30 m s 1... Conceptual Example 7 provides useful background for this problem. Workers have loaded a delivery truck in such a way that its center of gravity is only slightly forward of the rear axle, as shown in... You and your crew must dock your 25000 kg spaceship at Spaceport Alpha, which is orbiting Mars. In the process, Alphas control tower has requested that you ram another vessel, a freight ship of mass... Which quantity has the same unit as the rate of change of momentum? A. Acceleration B. Energy C. Weight D. Work Figure 6.18 shows the momentum vectors for two identical particles, 1 and 2, before and after a collision. Particle 2 was at rest before the collision. Show that momentum is conserved in this... Describe how to use a newton-meter, a micrometer screw gauge, a metal cube of side approximately 1.0 cm and a beaker of water to show experimentally that Archimedes principle is correct. The density... Explain why, in remote mountainous regions, such as the Hindu Kush, radio signals from terrestrial transmitters can be received, but television reception can only be received from satellite... The drawing below shows the overlap of two hybrid orbitals to form a bond in a hydrocarbon. (a) Which of the following types of bonds is being formed: (i) CC s, (ii) CC p or (iii) CH s? (b) Which of... An R-410a heat pump cycle shown in Fig. P4.123 has an R-410a flow rate of 0.1 lbm/s with 4 Btu/s into the compressor. The following data are given: Calculate the heat transfer from the compressor,... Make a control volume around the refrigerator in Fig. 1.3. Identify the mass flow of external air and show where you have significant heat transfer and where storage changes. Heat to room Warm vapor... We want to find the change in u for carbon dioxide between 50C and 200C at a pressure of 10 MPa. Find it using ideal gas and Table A.5, and repeat using the B section table. TABLE A.5 Properties of... More and more shoppers prefer to do their holiday shopping online from companies such as Amazon. Suppose we have a group of 10 shoppers; 7 prefer to do their holiday hopping online and 3 prefer to do... Buckeye Creek Amusement Park is open from the beginning of May to the end of October. Buckeye Creek relies heavily on the sale of season passes. The sale of season passes brings in significant... TourisTopia Travel (Triple T) is an online travel agency that specializes in trips to exotic locations around the world for groups of ten or more travelers. Triple Ts marketing manager has been... Use the information given in Table 3.6 on p. 43 to work out the formula for: a. Silver oxide b. Zinc chloride c. Potassium sulfate d. Calcium nitrate e. Iron(ii) nitrate f. Copper(ii) carbonate g.... A particle is placed on the inside of a rough, hollow cylinder of radius 2a. The cylinder is placed upright and 43 can rotate about an axis through its centre. The particle has mass in and the... A particle is placed on a rough horizontal disc, 2a from the centre of the disc. The particle is of mass 3m. The disc then starts to spin at an angular speed of g/4a. Given that the particle is on... Briefly distinguish between the following measures of variation: range, five-number summary, and standard deviation. Which one(s) can be represented with a boxplot? What do we mean when we say that distribution is skewed? Briefly describe the basic difference between a distribution that is skewed to the right and a distribution that is skewed to the left. For a recent year, baseball salaries had a median of $1,650,000 and a first quartile (Q1) of $1,675,000. Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly... I examined the data carefully, and the standard deviation was greater than the range Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does not... When taking a test for pregnancy, a true negative result is the same as a true positive result. It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true) or does... Theres much more variation in the ages of the general population than in the ages of students in my college extension course. Does It Make Sense? For Exercises, determine whether the statement makes... Listed below are the earnings (in millions of dollars) of the celebrities with the five highest incomes in a recent year. The celebrities in order are Steven Spielberg, Howard Stern, George Lucas,... Listed below are the numbers on the jerseys of the starting lineup for the New Orleans Saints when they won their first Super Bowl football game. Are the mean, median, and mode for these data... The histogram in Figure 4.12 shows the duration times of eruptions of the Old Faithful geyser in Yellowstone National Park. Eruptions of old Faithful 80 70 60 50 40 30 20 10 120 150 180 210 240 270... A sample of 39 ground beetles was captured from an area of waste ground measuring 100 25 metres. Each animal was marked and then released. A second sample of 35 was caught on the following day. Of... Light is an important abiotic factor that determines the distribution and abundance of plants. Some plants are adapted to grow in areas of low light intensity. They are known as shade plants. Some... What is the 68-95-99.7 rule for normal distributions? Does it apply to other (not normal) distributions as well? For a normal distribution, approximately what fraction of data values lie more than 1 standard deviation above the mean? When might data values be considered unusual? Explain. Woodlice are small terrestrial crustaceans that feed on organic matter in leaf litter and in the soil. While carrying out an ecological survey in woodland, a student noticed that there seemed to be... Stoneflies, Plecoptera spp., lay eggs in freshwater streams and rivers. The eggs hatch into nymphs which live in the water for several years before changing to adults. Stonefly nymphs are known as... The symbols below describe two isotopes of the element uranium. 235 92 U 238 92 U a. State the meaning of the term isotope. b. i. In what ways are these two isotopes of uranium identical? ii. In what... a. Describe the structure of an atom, giving details of the subatomic particles present. b. Explain the terms atomic number and nucleon number. c. Copy and complete the table: d. Explain why atoms... When ammonia gas and hydrogen chloride gas mix together, they react to form a solid called ammonium chloride. a. Write a balanced equation for this reaction, including state symbols. b. Calculate the... When sodium reacts with titanium chloride (TiCl 4 ), sodium chloride (NaCl) and titanium (Ti) are produced. a. Write the balanced symbol equation for the reaction. b. What mass of titanium is... Hydrocarbons are compounds of carbon and hydrogen only. Hydrocarbon Z is composed of 80% carbon and 20% hydrogen. a. Calculate the empirical formula of hydrocarbon Z. (A r values: C = 12.0, H = 1.0)... The graph shows a sketch of log 10 ionisation energy against number of electrons removed for magnesium. Use this sketch graph to answer the following questions. a. Explain why the first two electrons... Figure 3.37 depicts the amounts of daily oil consumption (in millions of barrels) in the United States and Japan. Does the illustration accurately depict the data? Why or why not? Daily Oil... The table below shows the 1st ionisation energies, H i1 , in kJ mol 1, of the elements in Period 3 of the Periodic Table. a. Explain why there is a general increase in the value of H i1 across the... a. The boiling points of the halogens are: fluorine 188 C chlorine 35 C bromine +59 C iodine +184 C i. Describe the trend in these boiling points going down Group 17. ii. Explain the trend in these... Aluminium chloride, AlCl 3 , and ammonia, NH 3 , are both covalent molecules. a. i. Draw a diagram of an ammonia molecule, showing its shape. Show any lone pairs of electrons. ii. State the bond... What is the distribution of data? Describe the important labels we should include when making a graph of a distribution? Finding that when tossing a coin, it turns up heads, given that it has turned up heads in the previous five tosses Theoretical Probabilities. For Exercises, use the theoretical method to determine... In New Jerseys Pick 4 lottery, you pay 50 to select a sequence of four digits, such as 2273, from the 10,000 different possible four-digit sequences. If you select the same sequence of four digits... The 50 songs on a smartphone consist of 15 that are rock, 20 that are jazz, and 15 that are country. Selections are played randomly and can be repeated. What is the probability of each of the... 1-bromobutane will undergo reactions when heated, as shown by reactions A and B. a. For reactions A and B give the reagents used in each case. b. Reaction A was repeated using 1-iodobutane instead of... I havent won in my last 25 pulls on the slot machine, so Im due to win on the next couple of pulls. Does It Make Sense? For Exercises, determine whether the statement makes sense (or is clearly true)... What does it mean when we write P(A)? What is the possible range of values for P(A), and why? This free-body diagram shows three forces that act on a stone hanging at rest from two strings. a. Calculate the horizontal component of the tension in each string. State why these two components are... The departure delay times (in minutes past the scheduled time) of Amtrak trains leaving New York City for Boston Normal Distributions. For each of the data sets in Exercises, state whether you would... The measured voltage amounts from newly manufactured AAA batteries made by Duracell Normal Distributions. For each of the data sets in Exercises, state whether you would expect it to be normally... This graph shows the variation of velocity with time of two cars, A and B, Which are travelling in the same direction over a period of time of 40 s. Car A, travelling at a constant velocity of 40 m s... A trolley travels along a straight track. The variation with time t of the velocity v of the trolley is shown. Which graph shows the variation with time of the acceleration a of the trolley? t Figure... Calculate the pH of a solution that is (a) 1.50 x 10 -1 M sulfamic acid. (b) 1.50 x 10 -2 M sulfamic acid. (c) 1.50 x 10 -4 M sulfamic acid. Motivated by a students death due to binge drinking, the College of Newport conducts a study of student drinking by randomly selecting 10 different classes and interviewing all of the students in... What does the square of the correlation coefficient, r2, tell us about a best-fit line? A microwave oven (Figure 13.9) uses microwaves with a wavelength of 12.5 cm. The front door of the oven is made of glass with a metal grid inside; the gaps in the grid are a few millimetres across.... The correlation I found was so strong that a careful calculation showed it had less than a 1 in 100,000 probability of occurring by chance. Therefore, I can reasonably conclude that one variable is... In a clinical trial, 11,000 male physicians were treated with aspirin and another 11,000 male physicians were given a placebo. A variable of interest was the proportion of heart attacks among the... In the circuit in Figure 23.18, the resistance has a resistance of 2000 , the capacitor has a capacitance of 1000 F and the battery has an e.m.f. of 12 V. a. Calculate: i. The potential difference... The area to the right of the standard score z = 1.0 is 0.1587, so the P-value in a two-tailed test is 0.1587.
Showing 1700 - 1800 of 4582