Which has more atoms: 1 kg of iron or 1 kg of aluminum? See t hcpha1nf 4u9);l8 x3c*k0 dbad5hyjx4y p+dkhe periodic table or Anc lx kpbk3+u* acx 5;hd44d8pad9 01 hyy)fjhppendix B.

Name several properties oid8/lg mg3oae; 2a kk8x ukk0)f materials that could be exploited to make a thermometer.;lik83/ ) ke8xk20goaum kagd

Which is larger, 1 C u39enz4wfajb5q - rez c( ctbgimw3n/:(n):l $^{\circ} $ or 1 F $^{\circ} $?

If system A is in therf m9+w*ui,; ;df beduomal equilibrium with system B, but B is not in thermal equilibrium with sy9ifuw ;+*ddoem;,u bf stem C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consist74;8yddewc4 .3 r hjybmbcu z1s of aluminum riveted to a strip of iron. When heated, the strip will bend. Which me1uzmdjdew7c 4b. h r 34byc8y;tal will be on the outside of the curve? [Hint: See Table 13–1.] Why?

In the relation $\Delta$L = $\alpha$ $L_0$ $\Delta$T, should $L_0$ be the initial length, the final length, or does it matter? Explain.

The units for the coefficient of linear expa0s k laqrz0u6 :9/c s91cjabbrjhyo/5 nsion $\alpha$ are $(C?)^{-1}$ and there is no mention of a length unit such as meters. Would the expansion coefficient change if we used feet or millimeters instead of meters? Explain.

Figure 13–27 shows a diagram of a simple thermostat used to contlf w:hgmphwb, 5 d8*hxrj i 877byrb6*rol a furnace (or other heating or cooling system). The bimetallicgdrj x87hwh * m7yrb if65 h8,p:*blbw strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury that conducts electricity when it can flow to touch both contact wires. Explain how this device controls the furnace and how it can be set at different temperatures.

Long steam pipes that are fixed at the ends often have a section in thtr1 w8x(ut09hzpgr nsdg. j(r4n*o j)e shape of a U. Why? tz.n0sun) jh(g(r4 rj 8wpg r*xtd91o

A flat, uniform cylinder of lead floats in mer946smg xipggf/*e6dcd*6 7uqll p 8u pcury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in;9sk 8e.tsqq h lzh*sha48roj+trm( ztl7u74-glass thermometer is first placed in a hot tub of water, the mercury initially descends a bit and then rises. Expl hsao js*hek.s8;z4 8ttll97z turr+q7h m( 4qain.

A glass container may break if one part of it is heated or cooled more rapica9lk2w n9/u xdly than adj/aux29lkcwn 9 acent parts. Explain.

The principal virtue of Pyrex glass is that iqdvbk-+38 oo +( qgokt0dwv/ots coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain(g+/v0d b+t8o - do3kq vokwoq why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accura1x m98cec)pckte at 20 $^{\circ} $ C, run fast or slow on a hot day (30 $^{\circ} $ C)? Explain. The clock uses a pendulum supported on a long, thin brass rod.

Freezing a can of soda will cause its bottom and top to bulge so j g-g-0 aew zzrdw.68ik;4 fnt0rgn(vbadly the can will not staaz vr kz(.wn0fg64r8jdgwi-;0gn- et nd up. What has happened?

When a gas is rapidly compressed (say, by pushing down a piston), its t/dvx 3:a7phsremperature increases. When d/7h:s prvax3a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in water increase zz5ozlkt3 x .xh c:m2 qixn3 *fl9te3zrl47i(or decrease ifxxxi3 7 l3fe:t( zzq zkrtc .2hz5mlion49*3l the temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic thtf3 )fk41wxt heory and the relation between averagtkhf)w tf134 xe kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinetic therbi l(;wime )ps) vz+.ory.

As you go higher in the Earth’s atmosphere, thiqf 8x9 /gtd5de ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object ,f1f 6sui0 (kq:f *fvdc6zsrdmust have to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth di u qf*d (fvc0 kf1,6z6dsr:fsue to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room tez)q3s ijx kq86j:31lr 7lhzk kmperature. What can you infer about the molecular propertii6qk lxj zl )7k3jq:831szkhr es of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dry day1/h gq+e 9akcg at the same temperahe k9cq/gg +a1ture.

Is it possible to boil water at *2y)ne-.efkv s )q8*etf:quf d)(x oucicgq+room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the 7*4 bp.b*zpwphlh gb2same but the humidity is different. Which i 2*zbwplhpg4 . pbh*7bs more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerousi+:zm0-e( 4 ,czzh uk 4mb*e7ppwjuqt to open the radiator cap of an overheated automobile engine.*imj0z :tzkqc(pup me7u z4bwe+- ,h 4

Why does exhaled air appear as a little wt59kl 2oi : nzzg-r8fzhite cloud in the winter (Fig. 13–28)?

  How many atoms are therex72rd v xx44dq in a 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ri/le n99xwsa+ ygcqw w() /pug0ng compare to the number in a silver y0g 9l/e q(cnxg +w)/u9s wwapring of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is t+1draem92+nkf + 72 em/ow:rmokvhehhis on the Celsius scale? edmn r vmko22r+eh+/hfa1o7:wkem9+   $^{\circ} $ C
(b) The temperature of the filament in a lightbulb is about 1800 $^{\circ} $ C. What is this on the Fahrenheit scale?    $^{\circ} $ F

  Among the highest and lowest temperatures reb nqd )u9h1:pip:u0 kdcorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

  (a) 15 $^{\circ} $ below zero on the Celsius scale is what Fahrenheit temperature?    $^{\circ} $ F
(b) 15 $^{\circ} $ below zero on the Fahrenheit scale is what Celsius temperature?   $^{\circ} $ C

  In an alcohol-in-glass thermometer, the alcoksekt)c; e2c pzh4z;0hol column has length 11.82 cm at 0.0cp tk)zkz4h ;cs2e;e0 $^{\circ} $ C and length 22.85 cm at 100.0 $^{\circ} $ C. What is the temperature if the column has length
(a) 16.70 cm,    $^{\circ} $ C
(b) 20.50 cm?    $^{\circ} $ C

  A concrete highway is built of sljl hb8uj9q,1ixh3-y(9k toy xabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

  Super Inva$^{TM}$, an alloy of iron and nickel, is a strong material with a very low coefficient of linear expansion [0.2$ \times10^{ -6}$(C?)$^{-1}$]
A 2.0-m-long tabletop made of this alloy is used for sensitive laser measurements where extremely high tolerances are required. How much will this table expand along its length if the temperature increases 5.0 $^{\circ} $ C? Compare to tabletops made of steel.   $ \times10^{-6 }$ m    $ \times10^{-4 }$ m

  The Eiffel Tower (Fig. 13–29) is built of w/h o2/w4cu vf8b( ltsfrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) and January (/ls ut/4(bfov8cw h f2average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, rivets that are larger than the rivet hole are often ubi(3jvcm io4ob ;j v-3sed and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in dij;jv 3i4cmb- (3oviob ameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water at k53rm ijd4g2.6es +*e q bbawa4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in volume if iy7b5owjpo)wg 4h/ /mc t is heated from 30moh5)/4 bopjw7g ycw/ $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of water at 13d-mj txfvx-l i4 v3-l ztaj*400.0$^{\circ} $ C. If the temperature decreased to 20.0 $^{\circ} $ C, how much water could be added to the glass?    mL

  It is observed that 55.50 mL eabpah/t/1j8 of water at 20 $^{\circ} $ C completely fills a container to the brim. When the container and the water are heated to 60 $^{\circ} $ C, 0.35 g of water is lost. (a) What is the coefficient of volume expansion of the container?    $ \times10^{-5 }$ /$C^0$(b) What is the most likely material of the container? The density of water at 60°C is 0.98324g/ml.

  (a) A brass plug is tlm0 o 0tmz.g;wc6 cm/wq81il5 ldnyf (o be placed in a ring made of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vessel so it can expand in5oyzavh 4do0mg :-+ hx essentially one moa5 h-hz+gd04 oyx:vdirection only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the den(x-gkv s awzz23d.p:h sity $\rho$ of a substance, when the temperature changes by $\Delta$T is given by $\rho$ = -$\beta$$\rho$$\Delta$T
(b) What is the fractional change in density of a lead sphere whose temperature decreases from 25 $^{\circ} $ C to -40 $^{\circ} $ C？

A uniform rectangular plate of length l at3krco jbkg6a1w -+g; nd width w has coefficient of linear expak3k w gtc-6j+1oa; bgrnsion $\alpha$ Show that, if we neglect very small quantities, the change in area of the plate due to a temperature change $\Delta$T is $\Delta$A = 2$\alpha l w$$\Delta$T See Fig. 13–30.

Show that for an isotropic gj x7c .e+4dpmsolid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made of brass and keeps perq9ku 9c0fnlmk2 rv 1s3fect time at 1 n9q9k c2lrm13vkf us07 $^{\circ} $ C. How much time is gained or lost in a year if the clock is kept at 25 $^{\circ} $ C? (Assume the frequency dependence on length for a simple pendulum applies.)$\approx$    min(Round to the nearest integer)

  (a) The tube of a mercury thermometer has abq 49dy;o v9q jyq fm32t4mjv8rz:8q qn inside diameter of 0.140 mm. The bulb has a volume of 0.2vq 8y9mqr 4dqm3jy4z8o9vjft :bq; 2q55 $cm^3$ How far will the thread of mercury move when the temperature changes from 11.5 $^{\circ} $ C to 33.0 $^{\circ} $ C? Take into account expansion of the Pyrex glass.    cm(b) Determine a formula for the length of the mercury column in terms of relevant variables. Ignore tube volume compared to bulb volume.

  A 23.4-kg solid aluminum cylibi*cn8p d/6kr ndrical wheel of radius 0.41 m is rotating about its axlebr n6id8k */pc on frictionless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desired length when at 15°C. How much stress is rek-ttkb* n c te91g xj8xi0t :,wxt6oc,quired to keep it at this length i tkgc8t* e0 cji:1 ,bkx, oxxt6-n9twtf the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-bearc.99 n ozk+oxm of cross-sectional area 0.041$m^2$ is rigidly connected to two vertical steel girders. If the beam was installed when the temperature was 30$^{\circ} $ C, what stress is developed in the beam when the temperature drops to -30 $^{\circ} $ C (b) Is the ultimate strength of the steel exceeded? (c) What stress is developed if the beam is concrete and has a cross-sectional area of 0.13$m^2$ Will it fracture?

  A barrel of diameter 134.122 cm at 2j-e 5zoc6fzl 3z+/e vx0$^{\circ} $ C is to be enclosed by an iron band. The circular band has an inside diameter of 134.110 cm at 20$^{\circ} $ C. It is 7.4 cm wide and 0.65 cm thick.
(a) To what temperature must the band be heated so that it will fit over the barrel? $\approx$   $^{\circ} $ C(Round to the nearest integer)
(b) What will be the tension in the band when it cools to 20$^{\circ} $ C?    N

  What are the following temperaturehrb3r+jw h27z s on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahrenheit scale? asj x 5;f qikek7/d;6nx/cdb3   $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun arjqgfr;jpez3v0 c9-q 3 e about 4000$^{\circ} $ C and $ \times10^{6 }$ $^{\circ} $ C respectively.
(a) What are these temperatures in kelvins?    K    $ \times10^{ 6}$K
(b) What percent error is made in each case if a person forgets to change $^{\circ} $ C to K? $\approx$    %(Round to the nearest integer) $\approx$    %(Round to three decimal places)

  If 3 $m^2$ of a gas initially at STP is placed under a pressure of 3.20 atm, the temperature of the gas rises to 38.0$^{\circ} $ C. What is the volume?    $m^3$

  In an internal combustion engine, air at atmospheric pressure and uf)l k65 acxaf)l-,s;.oy wrr a temperature of aa-rkc 5 uofw)x,) y6r .lfa;lsbout 20$^{\circ} $C is compressed in the cylinder by a piston to $\frac{1}{9}$ of its original volume (compression ratio = 9.0). Estimate the temperature of the compressed air, assuming the pressure reaches 40 atm.    $^{\circ} $ C

  Calculate the density of oxygen at STP using the ideal )415k(ifb6j5m md9bl fesfkb gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nq r4(uj q+oi(wdhs.*kitrogen ($N_2$) at an absolute pressure of 3.65 atm. What will the pressure be if the nitrogen is replaced by an equal mass of $CO_2$    atm

  A storage tank at STP contains 18.5 kznz 5;+:xuv4ghwf 9 rr 4vdo3hg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gasw- p)rp,xi4 cp1x+ cku is at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L container holding 105.0 kg of argon gas gg(f.e q 5p1ekat 38q51 fe.p(egkg 5 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg 1qup) ,ej l2rctby(n:v+v6ip of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air inside the balloo+1 jy,74zbxed2yuocpb: e gy;4 jrcm8 n, which makes it less dense than the air outside. Suppose the volumeyeprb je 8m, c;y cy7:odju24bxz1g4 + of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at 1g+;w of:eo ;qfyfp f3)5 $^{\circ} $ C to a gauge pressure of 220 kPa. If the tire reaches a temperature of 38 $^{\circ} $ C, what fraction of the original air must be removed if the original pressure of 220 kPa is to be maintained?    %

  If 61.5 L of oxygen at 18.03.7kao en -e-ndg9fzt $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled ball8 -g81jrwhlr toon escapes a child’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number of m csx5i:7w z9 f6fcarp*olecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water age saqpvb 1c9; /x7.xore there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of xceb*v3er*ph ,9q kk7a1wg :/ nlra+ j(a) moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5g -.ezxlqv*d a-ao-sdz)) l7z.1$ \times10^{ -2}m^3$ is filled with air at atmospheric pressure at 20 $^{\circ} $ C. The box is closed and heated to 180 $^{\circ} $ C. What is the net force on each side of the box?    N

  Estimate how many molecules of air are in each 2.0-L breath you inhale that:yqaq b )tj1;t were also in the last breath Galileo took. [Hint: Assume the atmosphere is about 10 km high and of const;tbjat q1):q yant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen moleculetz cdlcygw6mc v;86,wg..pd1 at STP? . gv, 6lmd8 gztwc;pdy1. wc6c   $ \times10^{-21 }$ J
(b) What is the total translational kinetic energy of 2.0 mol of $O_2$ molecules at 20 $^{\circ} $ C?   $ \times10^{3 }$ J

  Calculate the rms speed of helium atoms near the surface of thujrf5i+75d 9 ioejhc5iq2k9bks y *1me Sun at a temperature of about 6000 K. omqyj 5 esih51+bu9r7f5i2 9kci jd*k   m/s

  By what factor will the rms speed of gas molecules increase )xt) clou j04aif the temperature is increased fr0cu laj4xot))om 0 $^{\circ} $ C to 100 $^{\circ} $ C?   

  A gas is at 20 $^{\circ} $ C. To what temperature must it be raised to double the rms speed of its molecules?    $^{\circ} $ C

  Twelve molecules have the following speeds, given in unif 08tg l0f*nvmuf-7stts of km/s: 6, 2, 4, 6, 0, 4, 1, 0s*ffm0 u8- v7ngtflt 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules ;.s;h +nz4-o i9g:m pny.qtn o ktd)nein a gas at 20.0 $^{\circ} $ C is to be increased by 1.0%. To what temperature must it be raised?    $^{\circ} $ C

  If the pressure of a ga)d9j-zevbi4z7 y ,zonk*aj *l s is doubled while its volume is held constant, by what factor d)*o*nazyej k,9j-7b zivl 4z does $v_{rms}$ change?   

Show that the rms speed of molec6sjhv8i 1lzzlqz(t *vz.14do ules in a gas is given by $v_{rms}$ = $\sqrt{3P\\rho}$ where P is the pressure in the gas, and $\rho$ is the gas density.

Show that for a mixture of t.zbl*ywj j 1f0wo gases at the same temperature, the ratio of their rms speeds*bz jwj y1.0lf is equal to the inverse ratio of the square roots of their molecular masses.

  What is the rms speed t gr12rgqm nt3,wc/q(of nitrogen molecules contained in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed c9j0y .a f;ehzof an oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrogen molecules z0cam xrnrp6,f/d93na/v7j(c) f iw x1cks:i at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an t-1 *bka7zl awamino acid whose molecular mass is 89 u in a living cell -bw7k tal z1a*at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P 4v( dx je1,v izo*vp4oof a gas can be written P = $\frac(1)(3)\rho v^2$ where $\rho$ is the density of the gas and v is the rms speed of the molecules.

  The two isotopes of uraa0: cvbj6 rzwalk38 4+kifuktbm/sfpo7r 179nium, $^{235}$U and $^{238}$U (the superscripts refer to their atomic mass), can be separated by a gas-diffusion process by combining them with fluorine to make the gaseous compound UF$_6$ Calculate the ratio of the rms speeds of these molecules for the two isotopes, at constant T.   

(a) At atmospheric pressure, in- okus*to(v q7 what phases can $CO_2$ exist? (b) For what range of pressures and temperatures can $CO_2$ be a liquid? Refer to Fig. 13–21.

Water is in which phase when the pressure is 0.01 atm andzp/plz)x4c1 o. ky; fm the temperature is (a) 90 )cl k zxf/p.m4zoyp1;$^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day when thz+o ch(91j zxoe temperature is 29zozoch+(xj 15 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure ap24 fues7h cx*t a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a par2bhr5bcz xutj) j75hcsa -orp4s . z)93p:nqiticular place in the mountains is 0.72 atm, estimate the temperatu b3t7c hjr)5sp)j.o:sp ac2qz4-nub 5xrz ih9re at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial presy38-7o y :hrcdrd 3pjysure of water is 530 Pa and the rel r y yhd3yjc3r-7dp8:oative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature is 2b b fgbv/g8vn fj595m f-e)vk-5 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate up mj6gw-b4(h pressure inside a pressure cooker if the water is boiling at a temperature uj (m6-h 4pgbwof 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room xyn 7vw1bk rta49 m8a8of volume 680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its dew point+nmmrk w(4poi a-x90a of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Table 13–;;kur+g,g cws 4) to diffuse a diru+w;gcsg ,; kstance of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interi p5lyc; kw: 7:jd)cm9cmxgqe fn7h8m6or through tiny tubes called tracheae. An averagef6:5;w9qkl7 hj :e m7mxcmd 8pcn)cg y trachea is about 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calibrated afb1h+: -/ suw6 evgor6 zqjaq8t 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A precise steel tape measure has been calip :7; qa*mthm nt-ekm5, y5hywbrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at ncge e x3f 4;d8x(qxjv6ormal room temperature. How much error will be made in a recipe c qg63xe ;xf(jd8e4vxcalling for 300 mL of cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure i6o69n eijo7wijng82 rn a helium gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in thei oiogn68e 2j9j6r7n w cylinder?   

  Estimate the number of air moln0f( /4wwti ,)pmzhabyo m0w7o7 a3 xtecules in a room of length 6.5 m, width 3.1 m, and heiahni (z0 f m/b7mtwyw0)34px,oat o 7wght 2.5 m. Assume the temperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one atom per2q zafd3 5bjj6)chet/ $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure ow *w1eq,ei: p,6adhb attainable using the best available vacuum techniques is about: 6oedi q,*e,w 1bhwap $10^{-12} N/m^2$ At such a pressure, how many molecules are there per $cm^3$ at 0$^{\circ} $C?    $\frac{molecules}{cm^3}$

  If a scuba diver fills his lungs to full capacity of 5.5 L when 10 98k7sa aefg43dpu t .um below the surface, to what volum t4.a79ge fku8u s3dape would his lungs expand if he quickly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a speep*jcx kfr5 )4qd of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this qp 4c*5xf k)jrspeed correspond to what temperature? (Because of this high temperature, the nose of a space vehicle must be made of special materials; indeed, part of it does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increased from 1 jxqew u,+:b81pzomn 110$^{\circ} $C to 360$^{\circ} $C while the volume and the number of moles stay constant. By what factor does the pressure change? By what factor does $v_{rms}$ change?$\frac{P_2}{P_1}$ =    $\frac{(v_{rms})_2}{(v_{rms})_1}$ =   

  A house has a volume of 771v ,jo tg4z gis9-u u:ad7mhs50m$^2$ (a) What is the total mass of air inside the house at 20$^{\circ} $C?    kg
(b) If the temperature drops to -10$^{\circ} $C what mass of air enters or leaves the house?    kg

  From the known value of at0g8px.)gtu0/axk-lcyf )5ffpwr y u ;mospheric pressure at the surface of the Earth, estimate the total number of air molecules in the Earth’s atmosphere05xykg fyrufp-/f tp8u;lc .)0w xa) g.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules containedms. f:9cto7tf in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pressure = 244rd, dunig j1:hvz9 z000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atm:z1gnr 4zu4dh d,j9ivospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats 77br5dm. cnw rlbl(f7uil;x 3in a bowl of liquid mercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasol ,*aug(xq,elidr zp )-ine at 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around the Earth’s equatg4f.z i- 6hjator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tigpq r .jsysa+7+42jx6t1(c tv cvn,ucahtly onto a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length stand uwhvx 6)k-mr,ac vi; 7v*kpt9ard, adopted in the 18$^{th}$ century, was a platinum bar with two very fine marks separated by what was defined to be exactly 1 m. If this standard bar was to be accurate to within $\pm1.0 \mu m$ how carefully would the trustees have needed to control the temperature? The coefficient of linear expansion for platinum is $ 9\times10^{ -6}C/^{-1}$. $\pm$ =    C$^{\circ} $

  A scuba tank, when fully charged, has ;hmlbv0.kbah.s;kp ph . x,(gh* v.ur9d dsy.a pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the Earthh,(* ov:a yws7xau p/v is $ 1.12\times10^{4 } m/s$ so a gas molecule travelling away from Earth near the outer boundary of the Earth’s atmosphere would, at this speed, be able to escape from the Earth’s gravitational field. At what temperature is the average speed of
(a) oxygen molecules,    $ \times10^{5 }$K
(b) helium atoms equal to $ 1.12\times10^{4 } m/s$    $ \times10^{4}$K
(c) Can you see why our atmosphere contains oxygen but not helium?

  A 1.0-kg trash-can lid is suspendedmrvtrmm;u 6pg-atp y89 k:l8 4 against gravity by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from - 8gmklt8rva pr;96u p:4mtmythe lid elastically, assuming they have a mass of 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (sphern 4 h1q+kvgb+dical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as aghd4 n+v1+kbq perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the following two daysedb7i0z id 4h+j o2df)-ahwqnne, 1+f : ej 1bio0+if, han7)fd dz+q-hn dw42e
(a) a hot summer day, with the temperature 30$^{\circ} $C and the relative humidity at 40%;    Pa
(b) a cold winter day, with the temperature 5$^{\circ} $C and the relative humidity at 80%.    Pa

  A sauna has 7$m^3$ of air volume, and the temperature is 90$^{\circ} $C. The air is perfectly dry. How much water (in kg) should be evaporated if we want to increase the relative humidity from 0% to 10%? (See Table 13–3.)    kg

  Estimate the percent difference/ 4rdi-cj8 pwb in the density of iron at STP, and when it is a solid deep in the Earth wh/ rib4jc8d pw-ere the temperature is 2000$^{\circ} $C and under 5000 atm of pressure. Assume the bulk modulus (90$\times 10^9N/m^2$) and the coefficient of volume expansion do not vary with temperature and are the same as at STP.    %  ----待选择----decreaseincrease 

(a) Use the ideal gas law to show that, for an ideal gas at constantc(ho*h +nv(9b-px/jh 6g swjp pressure, the coefficientj+h/6p*h(g c xsvnbow p -9jh( of volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people constantly dehumidify their cellars to pv7ad kx9 3y/yabwgh53 revent rot and mildew. If the cellar iv9a7 a/hkyd3wx5 bg 3yn a house (kept at 20$^{\circ} $C) has 95 $m^2$ of floor space and a ceiling height of 2.8 m, what is the mass of water that must be removed from it to drop the humidity from 95% to a more reasonable 30%?    kg