Which has more atoms: 1 kg of iron or 1 kg of a0b-ug+qubsw7ro* m7ken;* u gluminum? See the periodic table or Appr0u ogesm- w ;7qb+k 7*nugub*endix B.

Name several propertxc c:aglha5en -k1 ye3/h)h4r ies of materials that could be exploited to make a thermomete cycheen hal5/a3) k:-4rhgx1r.

Which is larger, 1 C )lx5vkq q uae;/r.y86m7n9rrknd4 hy $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in t-llygfipi rwcj2w+ i,2) zt9 :hermal equilibrium with systejg:+ tw -9iplilrf2 2)i yc,zwm C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of all-+st exh.(3m qxuwo kji3*wij35 6nu uminum riveted to a strip of iron. When heated, the strip will bend. Which metal wil(xesi oj5h-jk6tun 3u+m*x3wq wl.i3 l 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 coeffn4t) gx:ojtzdi8c e,k- e) /fuicient of linear expansion $\alpha$ 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 tou, t 8wu arkd ..h2a+z4o1ccoo control a furnace (or oh+ r .c4 tozoc1,uada 2okwu.8ther heating or cooling system). The bimetallic 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 huy1q3; w43spndu8al9n n-w boften have a section in the shape of 9n ul- b1h3y wd3sqp nw8nua;4a U. Why?

A flat, uniform cylinder of lead flo 77 :vc(pu.j.3sl cjxdeeu3gv ats in mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed4k i::5wasqw0tq ryc+ in a hot tub of water, the mercury initially descends a bit and then rises. Expsq:y 4+wr iawc:5k q0tlain.

A glass container may break if,/oh+wbp lor * one part of it is heated or cooled more rapidly than adjacent parts. Eop*ho,wl br+/ xplain.

The principal virtue of Pyrex glass is that its coefficient of linear expansi(9zuvx6 t l1t lctt*5uon is much smaller than thatt(1tctu5 9*zl vxu 6tl for ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate at 27)a2jeulnu3fgj7 ,v 0p/ 7 omwuq+zst0 $^{\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 toqm *xyjd64fd b .wx:6w bulge so badly the can wid: bmqxx66f w*w 4jyd.ll not stand up. What has happened?

When a gas is rapidly compressed (say2: s*byh5yk* mfjhyd7 , by pushing down a piston), its temperatur2:f k7hym jsdhy*by5* e increases. When a 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 inu *7c 8bo4a+pu:wico kcrease or decrease if the temperature is incrb8 k4:*ucop c+i7 uwaoeased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the rela8nkz8 ona 7jo67.q j;xtrie1e tion bn8ek; e aor7n18q t.jio6x7jzetween average kinetic energy and the absolute temperature.

Explain in words how Gay-Lussxdrr(upe,e7;u e i1l lg0c2 4qac’s law follows from kinetic theory.

As you go higher in the) ;qwqt( 8g+edqa3 1qzgdsv+ )d2lhkw Earth’s atmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speed an object must have tpv-rnf*t+xt8 o leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due-8ntx tv*r+fp to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. What 9eo2wvnbg k. -,a*zive xq8e3can you infer about the molecular propertq, 2b* .vxgkovin-eawe98 3zeies of one relative to the other?

Explain why a hot humid lcm)494m lasiogt kx8*x*pu0r 1nl2 jday is far more uncomfortable than a hot dry day at the same temk9m **21 u80 l4jlcrmxxgn4oatispl )perature.

Is it possible to boil wate/oq:hmufuus0dy;s6ve 4 y)7pr at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temijwi 2bw41smumy +7b9hv* u2fperature is the same but the humidity is different. Whiim*s7fwj mbih+ 9w y v22bu1u4ch is more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous t4.+bhi 6da)ra (c+qo wja0epyo open the radiator cap of an overheated automobile engin(r0+pa ja w edchbaq 6o+i)4y.e.

Why does exhaled air appear as a little white cloud in the winter (Fig.+ ;8p0dh3 ; vueucn/ a-xbtv- km1rxta 13–28)?

  How many atoms are there in as0 zdki8 uw0;y 3.4-gram copper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to /2ogq zr*m 1iu-noj3slh-5 :te cj,zjthe number in a silver ring 2hjc1, -u/ 3j5lmrzgosni:-* ezjtqo of the same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is ofteele wn6. o 5tdo935brj7b4emoxid )e 9n taken to be 68°F. What is this on the Celsius scale? de99)od7bx4le3wtieoren 5om 6 b5j.   $^{\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 z 2p :req(m0wu+x1ci vrecorded 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 alcohol columu: q zb94un94iqpxa6gn has length 11.82 cm at 0.9 6iq zaubx n94pqg:u40 $^{\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 s(v d;eo/hrz1tx i:/k* y(bq eb;9lffylabs 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 builm rpfsrq 0g8yi8xask .;5;r o1t of wrought iron approximately 300 m tall. Estimate how much its height changes between 8oq agkfr5 8 x;s0.1rsyr;m ipJuly (average temperature of 25°C) and January (average 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 thajeth/d0x2u 9 zb :r6gw .m*jsen the rivet hole are often used jm2/g :weh.j s9*d zt6bx0uerand 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 diameter 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 v5 j forzehb9e5vx-7l*eq5t,4 $^{\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 diametergbnw5v /i:g 2g6hm-ke. What will be its change in volume if it is heated 56-m hgkv/ni g gb2e:wfrom 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with ( yv(3xc+ hakq350.0 mL of water at 100.0$^{\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 of water )5/zod sx5n; e0-pvidncebv,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 to be placed in a ring made o7s 7 xjk:lmpg oah445df 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 cf/wk fwiq:q+jf(q---s d h2mvan expand in essentially one direction only, show that the effective coefficient of linear expansion (fqwf:- -wj-qv sfqi+ hd/km2 is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in the de:kbm 46j wvhihnd*d*a*8( i vvnsity $\rho$ 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 and width w has coeff fr,v::nfjrwp3j72q xicient of linear expansion7vwqf:pf23,xjj rr: n $\alpha$ 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 sol; kqshn .yyooeg,26 h7id, $\beta$ = 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 andnbdh csm6wn u)yg+axd2f5, h4 5za,0e keeps perfect time at 17 x)+50,,4bdmzf6euyancn2d w g sahh5$^{\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 an in)aj, jwj1u4) ehecv5y9f9pvr side diameter of 0.140 mm. The bulb has a volumwhv5fcjj41,r99)jpu v ea )yee of 0.255 $cm^3$ 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 cylindrical wheel of radius 0.4pgw 8 86 3sriqz6jdcf.1 m is rotating about it fgjpdrw3sqz .868 6cis axle 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 deszj7fo 2hr0ndi +cffvm v6n)ah1)o),q ired length when at 15°C. How much stress is required to keep it at this length if the temperature increase)ood2 f7fzjc+vm1qr hf 6n 0hnai,v))s to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel;2/p3xhc zbcq; -bm/ w+kmgzp I-beam 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 2tr whjuy62c8x 17igf0j ;f3ug0$^{\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 followirf:mi b/z *b e/tfq+t-ng temperatures 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 temperature4zu( 6+yiry j(*cwayp on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are about 409i.wiika w4 9i00$^{\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 pres*pl90 je bniea4t 6.z8t+jiltsure and a temperature of about j0aetn +l*t.ie j69bp8 zi4lt 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*ymo bl,vk2 k jdk6-q- the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg vu,6 2h j wptc73kt/toof nitrogen ($N_2$) 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 contaxhk.o+gx/lo v q2u s:9ins 18.5 kg 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 gas is 8ipjv ft7hw9: 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 ae80 we++ nfkqxu24sv irgon gas at 385 K4vn2+ kif0+exwsq u8e?   $ \times10^{ 8}$Pa

  A tank contains 26.0 u3gebxw j8q1 9kg 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 heatiy. jiu.se y2ki/s,p 7dng the air inside the balloou i,se7 .jd2si./ky ypn, which makes it less dense than the air outside. Suppose the volume 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 aireo5+bm gkq*8.r bpwbtxh4 4k6 at 15 $^{\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 18.0 yf ) mwgd+vl:v b2vm5)$^{\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 balloon escapn8j7eeea-n0i dw/3sigr.e 4ah(z :4x afym o9es 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;urbp9k uo4d :l 95zh gi5gckj:+8 oqi of molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are * vptw9ywt50v there in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) molidxx l14ctp a7o:d1 5yocb y9/es,    $ \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 5dtfrn n.lb 3h:)7ft- m.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 mo)mi-sy,rk)byh(5 u krlecules of air are in each 2.0-L breath you inhale that were also in the last breath Galilekm5)-rybh,)( ik yrs uo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic eu ur rw;+ wfqkft,w8q(;w.p.fnergy of an oxygen molecule at STPwuwtf(w,8r ;qf.ufq+ prkw;.?    $ \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 t hp)h7ishza: lepu6, tu:,fddhu9d/ld (/d6 ahe surface of the Sun at a temperature of about 600l:d hail:e6, pz utd / p9h76ahfsudhd),( du/0 K.    m/s

  By what factor will the rms speed of gas molecunlwy0*7:ogpzra xe*f 4u5 n/qles increase if the temperature is x5/eu:npalgny7f *qz * o0wr 4increased from 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 followinjxk,ucv+56j 0hjyq/8 ox6axg g speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1joxvj8 6 j+xa5yqguhx,6 ck0/, 8, 5, 3, 7, and 8. Calculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a ga u1 +*x0ojn80wcjh *6b;abjtfanny0 ws 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 gas is doubled while its volume is hev/jbhcjkt , -bz 9ma92h 1pgxq p8+4hvld constant, by what factor does /j28z -+m9kpphh,b j1xbv a cqtvh 9g4$v_{rms}$ change?   

Show that the rms speed of molecules inzxz0:mur5q8 mij,q:t 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 two gasr/i ri,; 8l(hphhejg4es at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the square rhh8 ihe/(,gp4 rr ;jlioots of their molecular masses.

  What is the rms speed of nitrogen molecules contagr8vqv*+f1lo* m f6bq ined 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 of(rbfk oueix-:cy*a + 9 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 at . lp vczmzybld j48u6/u:6 5xlSTP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of ptl hl/)jh 5h/hku6f66:2wosn*wmrg an amino acid whose molecular mass is 89 u in a living cell a fh6)2 wmhsr:u6//nh kjh ol6l*wgp5 tt 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 pressu )tusca6xsa:a flzp2 4ap *2k7re P of 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 uran h h9tvgwr;r2:ium, $^{235}$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 .o1ybjh:.hrjqd 1 5iowhat 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 and the temfqm fskr58b,w8g .h6g perature is (a) 90.85 rfqkwsfmg, b68 gh $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day whe c+6l/-k juv2zndaz ykd4p 3l im+ve0:n the temperature ik3zez+2k v60 j4lu -ydamnip+dcl /:v s 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where waterak yob2(*tu tubklp-;vs. u/6 boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountainsjp td96z lsd h2gr fiq3s373/m is 0.72 atm, estimate the temperature ahms7i36z/g rjlq9f 3dtp3s2dt which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pre 8nv4vm1g hy,wrg47 wos )nng;ssure of water is 530 Pa and the relative humidity is 40%?)hs1 ;w g4onnv4wv 87r,ynggm $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature .j.bbas0 k hyv,qct;wg9). qae qg;d7 is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure incllkys m ;5e3/side a pressure cooker if the water is boilin35 /k sclm;lyeg at a temperature of 120 $^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room ofqf vs7a/tq)( s 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 oo:z:ed3nr6 j +e:z4ioa+tjgpoint 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 forgust5j/8 d 6bf a glycine molecule (see Table 13–4) to diffuse a distance ojfsd t6/g5ub8f 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 thej4t 77vi5a5 lo 9*o mvv(sy*dvwvo 0xq interior through tiny tubes callel05j5v o wv*qavm*vo(yi747dts vox9d tracheae. An average 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 calrqv5 /5 vqknow-(.lsrmb) lw +ibrated 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 precise steel tape measu / 6 3orqi2vojgvn6h*rre has been calibrated 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 normal room temperature. How mucuo 1 ci:-vr5nah error will bu1 nv:o-acr5ie made in a recipe calling 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 in a helium gas cylinder is initially 28 atm. After :/jo2 bpndl y z9 igy;vr9*bn4a o tf*rl4-lw.many balloons have been blown up, the gauge pressure has decreasedpz.- 94;lvbolfj*yrwr2lyn:*/ dni b 49 toag to 5 atm. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of len+dttbgs vc ;)j,mej88gth 6.5 m, width 3.1 m, and heijmb;dt +),88cvt ejg sght 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 ofes1f5 gz37 5 fqo9qhuf matter is about one atom per $cm^3$ 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 attainable using the best available vacuum techniques in w.*l par-eo,11yew24a4nekqr .* mj jtk*xls about j 4 rlw4kt*1r*,x1.lejo.anqen-kwma e *py2 $10^{-12} N/m^2$ 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 m below thj4j iywjnl5.zf-qt 10 i1vn5ue surface, to what volume would his lungs expand if he quickly rose town4lj5 niyv i-uq1j.t0z5j1 f the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a sb1odqd4 hc) zqb*(9er-g rls;peed of about 40,000 km/h Molecules (assume nitrogen) striking the nose of the vehicle with this speed 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 doesszrb ; dld)h-b(9q1r o4ecg q* vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal go.ybx 814i mtt;9.curm/ppb gas is increased from 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 ofzeg5 8ly3ygsd8kltoq h 8. m/9 770m$^2$ (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 atmospheric pressure at the sur)q 0l xi-x+rwlface of the Earth, estimate the total number of air molecu 0xq xrl)+ilw-les in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitror a1h1,ef)hqj gen molecules contained 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 gaaz: g2ztin9cl df4 qfrun5;ff7:4ew7 uge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2d e7z:lfg247tncniufq a w4f;59 :frz.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury at p h4jt4b qf;+b0$^{\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 gasoline at krn;82adv b r.ip3o4o0$^{\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 eq l49bad jhtqol+-y1-e uator 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 tightly onto a glass jar go*s; j-au qz6q +fj(cat 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 standard, adopted in the 18f*fy 3r 9b- rk,expsp4f j76yx$^{th}$ 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 f*w* o o.yqwqoj8g.oq bkk:/ b;ully charged, has 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 Earths1 xs o0wstn,. 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 suspended against gravity by tennis balls throwngozayb)6 j* s(2rrgf ; vertically upward at it. Howrga; oj6g f*z)2by(sr many tennis balls per second must rebound from the 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-diame/qdo dphkowm4a2oih+ : cm)z .ex1em; gy4 i)(ter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature is constant at 298 adowomykqg)2 mz4d(; eh. io:p/i +mhxe)c14K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressomvw ;bkizswq 3)50+iure in the air on the following two days: moz i);53vksw+wbi0 q
(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 in the density of iron at STP, and when x ie56cy0:d g g8hf)+9ktvlxwit is a solid deep in the Earth where the temperature is 8yeg :xw09l5v f6x)d chtkgi+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 la.bjxsur td-t1njl a 9;) jtt5-w to show that, for an ideal gas at constant pressure, the coefficient of volume expansion is equaltlur- jdt b5s- tt)aj9;jxn1. 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 dehumidifcfb(xso,hg4qp3s a 6(y their cellars to prevent rot and mildew. If the cellar in a house (kept at 20 s(so4,xcbg3 qfh 6ap($^{\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