2.99 See Answer

Question: Formaldehyde has the chemical formula CH2O.


Formaldehyde has the chemical formula CH2O. Calculate the number of
(a) Moles, and
(b) CH2O molecules in 275 g of formaldehyde.


> If the amplitude of a system moving in simple harmonic motion is doubled, which of the following quantities doesn’t change? (a) Total energy (b) Maximum speed (c) Maximum acceleration (d) Period

> Consider the situation in Quick Quiz 13.4. Is the subsequent total mechanical energy of the object with mass 4m (a) Greater than, (b) Less than, or (c) Equal to the original total mechanical energy? Quick Quiz 13.4: An object of mass m is attached to a

> A 75-kg cross-country skier glides over snow as in Figure P11.33. The coefficient of friction between skis and snow is 0.20. Assume all the snow beneath her skis is at 0°C and that all the internal energy generated by friction is added to snow

> An object of mass m is attached to a horizontal spring, stretched to a displacement A from equilibrium, and released, undergoing harmonic oscillations on a frictionless surface with period T0. The experiment is then repeated with a mass of 4m. What’s the

> When an object moving in simple harmonic motion is at its maximum displacement from equilibrium, which of the following is at a maximum? (a) Velocity, (b) Acceleration, or (c) Kinetic energy

> For a simple harmonic oscillator, which of the following pairs of vector quantities can’t both point in the same direction? (The position vector is the displacement from equilibrium.) (a) Position and velocity (b) Velocity and acceleration (c) Position a

> A block on the end of a horizontal spring is pulled from equilibrium at x = 0 to x = A and released. Through what total distance does it travel in one full cycle of its motion? (a) A/2 (b) A (c) 2A (d) 4A

> Suppose you are throwing two dice in a friendly game of craps. For any given throw, the two numbers that are faceup can have a sum of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12. Which outcome is most probable? Which is least probable?

> Which of the following is true for the entropy change of a system that undergoes a reversible, adiabatic process? (a) ΔS < 0 (b) ΔS = 0 (c) ΔS > 0

> Three engines operate between reservoirs separated in temperature by 300 K. The reservoir temperatures are as follows: Engine A: Th = 1 000 K, Tc = 700 K Engine B: Th = 800 K, Tc = 500 K Engine C: Th = 600 K, Tc = 300 K Rank the engines in order of their

> Identify the paths A, B, C, and D in Figure 12.11 as isobaric, isothermal, isovolumetric, or adiabatic. For path B, Q = 0. Figure 12.11:

> By visual inspection, order the PV diagrams shown in Figure 12.5 from the most negative work done on the system to the most positive work done on the system. (a) a, b, c, d (b) a, c, b, d (c) d, b, c, a (d) d, a, c, b Figure 12.5:

> Stars A and B have the same temperature, but star A has twice the radius of star B. (a) What is the ratio of star A’s power output to star B’s output due to electromagnetic radiation? The emissivity of both stars can be assumed to be 1. (b) Repeat the qu

> How much energy is required to change a 40.-g ice cube from ice at -10.°C to steam at 110.°C?

> Two rods of the same length and diameter are made from different materials. The rods are to connect two regions of different temperature so that energy will transfer through the rods by heat. They can be connected in series, as in Figure 11.7a, or in par

> Will an ice cube wrapped in a wool blanket remain frozen for (a) Less time, (b) The same length of time, or (c) A longer time than an identical ice cube exposed to air at room temperature?

> The boiling point of liquid hydrogen is 20.3 K at atmospheric pressure. What is this temperature on (a) The Celsius scale and (b) The Fahrenheit scale?

> The pressure in a constant-volume gas thermometer is 0.700 atm at 1.00 x 102°C and 0.512 atm at 0°C. (a) What is the temperature when the pressure is 0.0400 atm? (b) What is the pressure at 450°C?

> Long-term space missions require reclamation of the oxygen in the carbon dioxide exhaled by the crew. In one method of reclamation, 1.00 mol of carbon dioxide produces 1.00 mol of oxygen, with 1.00 mol of methane as a by-product. The methane is stored in

> A 1.5-m-long glass tube that is closed at one end is weighted and lowered to the bottom of a freshwater lake. When the tube is recovered, an indicator mark shows that water rose to within 0.40 m of the closed end. Determine the depth of the lake. Assume

> A steel beam being used in the construction of a skyscraper has a length of 35.000 m when delivered on a cold day at a temperature of 15.000°F. What is the length of the beam when it is being installed later on a warm day when the temperature is 90.000°F

> Consider an object with any one of the shapes displayed in Table 8.1. What is the percentage increase in the moment of inertia of the object when it is warmed from 0&Acirc;&deg;C to 100.&Acirc;&deg;C if it is composed of (a) Copper or (b) Aluminum? Assum

> A popular brand of cola contains 6.50 g of carbon dioxide dissolved in 1.00 L of soft drink. If the evaporating carbon dioxide is trapped in a cylinder at 1.00 atm and 20.0°C, what volume does the gas occupy?

> The active element of a certain laser is made of a glass rod 30.0 cm long and 1.50 cm in diameter. Assume the average coefficient of linear expansion of the glass is 9.00 x 10-6 (°C)-1. If the temperature of the rod increases by 65.0°C, what is the incre

> A 100.-g cube of ice at 0°C is dropped into 1.0 kg of water that was originally at 80.°C. What is the final temperature of the water after the ice has melted?

> Inside the wall of a house, an L-shaped section of hot-water pipe consists of three parts: a straight horizontal piece h = 28.0 cm long, an elbow, and a straight, vertical piece &acirc;&#132;&#147; = 134 cm long (Fig. P10.51). A stud and a second-story f

> In a period of 1.0 s, 5.0 x 1023 nitrogen molecules strike a wall of area 8.0 cm2. If the molecules move at 3.00 x 102 m/s and strike the wall head-on in a perfectly elastic collision, find the pressure exerted on the wall. (The mass of one N2 molecule i

> Superman leaps in front of Lois Lane to save her from a volley of bullets. In a 1-minute interval, an automatic weapon fires 150 bullets, each of mass 8.0 g, at 4.00 x 102 m/s. The bullets strike his mighty chest, which has an area of 0.75 m2. Find the a

> A 7.00-L vessel contains 3.50 moles of ideal gas at a pressure of 1.60 x 106 Pa. Find (a) The temperature of the gas and (b) The average kinetic energy of a gas molecule in the vessel. (c) What additional information would you need if you were asked to f

> At what temperature would the rms speed of helium atoms equal (a) The escape speed from Earth, 1.12 x 104 m/s and (b) The escape speed from the Moon, 2.37 x 103 m/s? Note: The mass of a helium atom is 6.64 x 10-27 kg.

> Two gases in a mixture pass through a filter at rates proportional to the gases’ rms speeds. (a) Find the ratio of speeds for the two isotopes of chlorine, 35Cl and 37Cl, as they pass through the air. (b) Which isotope moves faster?

> Use Avogadro’s number to find the mass of a helium atom.

> A sealed cubical container 20.0 cm on a side contains a gas with three times Avogadro’s number of neon atoms at a temperature of 20.0°C. (a) Find the internal energy of the gas. (b) Find the total translational kinetic energy of the gas. (c) Calculate th

> Three moles of an argon gas are at a temperature of 275 K. Calculate (a) The kinetic energy per molecule, (b) The rootmean- square (rms) speed of an atom in the gas, and (c) The internal energy of the gas.

> Calculate the root-mean-square (rms) speed of methane (CH4) gas molecules at a temperature of 325 K.

> A 50.-kg ice cube at 0°C is heated until 45 g has become water at 100.°C and 5.0 g has become steam at 100.°C. How much energy was added to accomplish the transformation?

> Why is it important to avoid sharp edges or points on conductors used in high-voltage equipment?

> What is the average kinetic energy of a molecule of oxygen at a temperature of 300. K?

> During inhalation, a person’s diaphragm and intercostal muscles contract, expanding the chest cavity and lowering the internal air pressure below ambient so that air flows in through the mouth and nose to the lungs. Suppose a person’s lungs hold 1250 mL

> An air bubble has a volume of 1.50 cm3 when it is released by a submarine 1.00 x 102 m below the surface of a lake. What is the volume of the bubble when it reaches the surface? Assume the temperature and the number of air molecules in the bubble remain

> The density of helium gas at 0°C is p0 = 0.179 kg/m3. The temperature is then raised to T = 100°C, but the pressure is kept constant. Assuming the helium is an ideal gas, calculate the new density pf of the gas.

> A weather balloon is designed to expand to a maximum radius of 20 m at its working altitude, where the air pressure is 0.030 atm and the temperature is 200 K. If the balloon is filled at atmospheric pressure and 300 K, what is its radius at liftoff?

> Gas is contained in an 8.00-L vessel at a temperature of 20.0°C and a pressure of 9.00 atm. (a) Determine the number of moles of gas in the vessel. (b) How many molecules are in the vessel?

> Gas is confined in a tank at a pressure of 11.0 atm and a temperature of 25.0°C. If two-thirds of the gas is withdrawn and the temperature is raised to 75.0°C, what is the new pressure of the gas remaining in the tank?

> An automobile tire is inflated with air originally at 10.0°C and normal atmospheric pressure. During the process, the air is compressed to 28.0% of its original volume and the temperature is increased to 40.0°C. (a) What is the tire pressure in pascals?

> (a) An ideal gas occupies a volume of 1.0 cm3 at 20.°C and atmospheric pressure. Determine the number of molecules of gas in the container. (b) If the pressure of the 1.0-cm3 volume is reduced to 1.0 x 10-11 Pa (an extremely good vacuum) while the temper

> A container holds 0.500 m3 of oxygen at an absolute pressure of 4.00 atm. A valve is opened, allowing the gas to drive a piston, increasing the volume of the gas until the pressure drops to 1.00 atm. If the temperature remains constant, what new volume d

> A 75-kg sprinter accelerates from rest to a speed of 11.0 m/s in 5.0 s. (a) Calculate the mechanical work done by the sprinter during this time. (b) Calculate the average power the sprinter must generate. (c) If the sprinter converts food energy to mecha

> One mole of oxygen gas is at a pressure of 6.00 atm and a temperature of 27.0°C. (a) If the gas is heated at constant volume until the pressure triples, what is the final temperature? (b) If the gas is heated so that both the pressure and volume are doub

> A sample of pure copper has a mass of 12.5 g. Calculate the number of (a) Moles in the sample and (b) Copper atoms in the sample.

> The concrete sections of a certain superhighway are designed to have a length of 25.0 m. The sections are poured and cured at 10.0°C. What minimum spacing should the engineer leave between the sections to eliminate buckling if the concrete is to reach a

> Figure P10.27 shows a circular steel casting with a gap. If the casting is heated, (a) Does the width of the gap increase or decrease? (b) The gap width is 1.600 cm when the temperature is 30.0&Acirc;&deg;C. Determine the gap width when the temperature i

> The density of gasoline is 7.30 x 102 kg/m3 at 0°C. Its average coefficient of volume expansion is 9.60 x 10-4(°C)-1, and note that 1.00 gal = 0.00380 m3. (a) Calculate the mass of 10.0 gal of gas at 0°C. (b) If 1.000 m3 of gasoline at 0°C is warmed by 2

> The average coefficient of volume expansion for carbon tetrachloride is 5.81 x 10-4 (°C)-1. If a 50.0-gal steel container is filled completely with carbon tetrachloride when the temperature is 10.0°C, how much will spill over when the temperature rises t

> The Trans-Alaskan pipeline is 1300 km long, reaching from Prudhoe Bay to the port of Valdez, and is subject to temperatures ranging from -73°C to +35°C. (a) How much does the steel pipeline expand due to the difference in temperature? (b) How can one com

> The band in Figure P10.23 is stainless steel (coefficient of linear expansion = 17.3 x 10-6 (&Acirc;&deg;C)-1; Young&acirc;&#128;&#153;s modulus = 18 x 1010 N/m2). It is essentially circular with an initial mean radius of 5.0 mm, a height of 4.0 mm, and

> A construction worker uses a steel tape to measure the length of an aluminum support column. If the measured length is 18.700 m when the temperature is 21.2°C, what is the measured length when the temperature rises to 29.4°C? Note : Don’t neglect the exp

> A 75-g ice cube at 0°C is placed in 825 g of water at 25°C. What is the final temperature of the mixture?

> A hollow aluminum cylinder 20.0 cm deep has an internal capacity of 2.000 L at 20.0°C. It is completely filled with turpentine at 20.0°C. The turpentine and the aluminum cylinder are then slowly warmed together to 80.0°C. (a) How much turpentine overflow

> Show that the coefficient of volume expansion, β, is related to the coefficient of linear expansion, α, through the expression β = 3α.

> An underground gasoline tank can hold 1.00 x 103 gallons of gasoline at 52.0°F. If the tank is being filled on a day when the outdoor temperature (and the gasoline in a tanker truck) is 95.0°F, how many gallons from the truck can be poured into the tank?

> The Golden Gate Bridge in San Francisco has a main span of length 1.28 km, one of the longest in the world. Imagine that a steel wire with this length and a cross-sectional area of 4.00 x 10-6 m2 is laid on the bridge deck with its ends attached to the t

> The density of lead is 1.13 x 104 kg/m3 at 20.0°C. Find its density at 105°C.

> A wire is 25.0 m long at 2.00°C and is 1.19 cm longer at 30.0°C. Find the wire’s coefficient of linear expansion.

> A brass ring of diameter 10.00 cm at 20.0°C is heated and slipped over an aluminum rod of diameter 10.01 cm at 20.0°C. Assuming the average coefficients of linear expansion are constant, (a) To what temperature must the combination be cooled to separate

> A spherical steel ball bearing has a diameter of 2.540 cm at 25.00°C. (a) What is its diameter when its temperature is raised to 100.0°C? (b) What temperature change is required to increase its volume by 1.000%?

> A pair of eyeglass frames are made of epoxy plastic (coefficient of linear expansion = 1.30 x 10-4 (°C)-1). At room temperature (20.0°C), the frames have circular lens holes 2.20 cm in radius. To what temperature must the frames be heated if lenses 2.21

> A grandfather clock is controlled by a swinging brass pendulum that is 1.3 m long at a temperature of 20.0°C. (a) What is the length of the pendulum rod when the temperature drops to 0.0°C? (b) If a pendulum’s period is given by T = 2π√L/g, where L is it

> How much thermal energy is required to boil 2.00 kg of water at 100.0°C into steam at 125°C? The latent heat of vaporization of water is 2.26 x 106 J/kg and the specific heat of steam is 2010 J/(kg ∙ °C).

> The New River Gorge bridge in West Virginia is a 518-m-long steel arch. How much will its length change between temperature extremes of -20.0°C and 35.0°C?

> Temperature differences on the Rankine scale are identical to differences on the Fahrenheit scale, but absolute zero is given as 0°R. (a) Find a relationship converting the temperatures TF of the Fahrenheit scale to the corresponding temperatures TR of t

> A nurse measures the temperature of a patient to be 41.5°C. (a) What is this temperature on the Fahrenheit scale? (b) Do you think the patient is seriously ill? Explain.

> The temperature difference between the inside and the outside of a home on a cold winter day is 57.0°F. Express this difference on (a) The Celsius scale and (b) The Kelvin scale.

> A person’s body temperature is 101.6°F, indicating a fever of 3.0°F above the normal average body temperature of 98.6°F. How many degrees above normal is this body temperature on the Celsius scale?

> In a student experiment, a constant-volume gas thermometer is calibrated in dry ice (-78.5°C) and in boiling ethyl alcohol (78.0°C). The separate pressures are 0.900 atm and 1.635 atm. (a) What value of absolute zero in degrees Celsius does the calibrati

> On January 22, 1943, in Spearfish, South Dakota, the temperature rose from -4.00°F to 45.0°F over the course of two minutes (the current world record for the fastest recorded temperature change). By how much did the temperature change on the Kelvin scale

> Death Valley holds the record for the highest recorded temperature in the United States. On July 10, 1913, at a place called Furnace Creek Ranch, the temperature rose to 134°F. The lowest U.S. temperature ever recorded occurred at Prospect Creek Camp in

> Two resistors connected in series have an equivalent resistance of 690 Ω. When they are connected in parallel, their equivalent resistance is 150 Ω. Find the resistance of each resistor.

> Consider the combination of resistors shown in Figure P18.8. a) Find the equivalent resistance between point a and b. (b) If a voltage of 35.0 V is applied between points a and b, find the current in each resistor. Figure P18.8:

> Suppose 9.30 x 105 J of energy are transferred to 2.00 kg of ice at 0°C. (a) Calculate the energy required to melt all the ice into liquid water. (b) How much energy remains to raise the temperature of the liquid water? (c) Determine the final temperatur

> (a) Find the equivalent resistance between points a and b in Figure P18.7. (b) Calculate the current in each resistor if a potential difference of 34.0 V is applied between points a and b. Figure P18.7:

> Three 9.0 - Ω resistors are connected in series with a 12 - V battery. Find (a) The equivalent resistance of the circuit and (b) The current in each resistor. (c) Repeat for the case in which all three resistors are connected in parallel across the batte

> Two resistors, R1 and R2, are connected in series. (a) If R1 = 2.00 Ω and R2 = 4.00 Ω, calculate the single resistance equivalent to the series combination. (b) Repeat the calculation for a parallel combination of R1 and R2.

> A battery with a 0.100 - Ω internal resistance supplies 15.0 W of total power with a 9.00 V terminal voltage. Determine (a) The current I and (b) The power delivered to the load resistor.

> A battery with an emf of 12.0 V has a terminal voltage of 11.5 V when the current is 3.00 A. (a) Calculate the battery’s internal resistance r. (b) Find the load resistance R.

> (a) Find the current in an 8.00 - Ω resistor connected to a battery that has an internal resistance of 0.15 V if the voltage across the battery (the terminal voltage) is 9.00 V. (b) What is the emf of the battery?

> A battery with &Icirc;&micro; = 6.00 V and no internal resistance supplies current to the circuit shown in Figure P18.14. When the double - throw switch S is open as shown in the figure, the current in the battery is 1.00 mA. When the switch is closed in

> The resistance between terminals a and b in Figure P18.13 is 75 &Icirc;&copy;. If the resistors labeled R have the same value, determine R. Figure P18.13:

> Four resistors are connected to a battery as shown in Figure P18.12. (a) Determine the potential difference across each resistor in terms of &Ntilde;&#148;. (b) Determine the current in each resistor in terms of I. Figure P18.12:

> Consider the circuit shown in Figure P18.11. Find (a) The potential difference between points a and b and (b) The current in the 20.0 - &Icirc;&copy; resistor. Figure P18.11:

> An unknown substance has a mass of 0.125 kg and an initial temperature of 95.0 °C. The substance is then dropped into a calorimeter made of aluminum containing 0.285 kg of water initially at 25.0 °C. The mass of the aluminum container is 0.150 kg, and th

> Consider the circuit shown in Figure P18.10. (a) Calculate the equivalent resistance of the 10.0 - &Icirc;&copy; and 5.00 - &Icirc;&copy; resistors connected in parallel. (b) Using the result of part (a), calculate the combined resistance of the 10.0 - &

> A battery having an emf of 9.00 V delivers 117 mA when connected to a 72.0 - Ω load. Determine the internal resistance of the battery.

> An iron wire has a cross - sectional area of 5.00 x 10-6 m2. Carry out steps (a) through (e) to compute the drift speed of the conduction electrons in the wire. (a) How many kilograms are there in 1 mole of iron? (b) Starting with the density of iron and

> An aluminum wire having a cross - sectional area of 4.00 x 10-6 m2 carries a current of 5.00 A. The density of aluminum is 2.70 g/cm3. Assume each aluminum atom supplies one conduction electron per atom. Find the drift speed of the electrons in the wire.

> A 2.0 x 102 - km - long high - voltage transmission line 2.0 cm in diameter carries a steady current of 1.0 x 103 A. If the conductor is copper with a free charge density of 8.5 x 1028 electrons/m3, how many years does it take one electron to travel the

> A man wishes to vacuum his car with a canister vacuum cleaner marked 535 W at 120. V. The car is parked far from the building, so he uses an extension cord 15.0 m long to plug the cleaner into a 120. - V source. Assume the cleaner has constant resistance

> An x - ray tube used for cancer therapy operates at 4.0 MV, with a beam current of 25 mA striking the metal target. Nearly all the power in the beam is transferred to a stream of water flowing through holes drilled in the target. What rate of flow, in ki

> When a straight wire is heated, its resistance changes according to the equation R = R0[1 + &Icirc;&plusmn;(T - T0)] (Eq. 17.7), where &Icirc;&plusmn; is the temperature coefficient of resistivity. (a) Show that a more precise result, which includes the

> A resistor is constructed by forming a material of resistivity 3.5 x 105 Ω · m into the shape of a hollow cylinder of length 4.0 cm and inner and outer radii 0.50 cm and 1.2 cm, respectively. In use, a potential difference is applied between the ends of

2.99

See Answer