Which has more atoms: 1 kg of iron or 1 kg of aluminum? See thsb (g2w/mz3cbe periodic table ob( sz/c mw3bg2r Appendix B.

Name several properties of m aq/jq;fa0a p:qy 6fzh+t4+,iry(bh t 66lfai aterials that could be exploited to make a thermometerq pl0hh+aitftb q+f :aqa6; i, 64yj y/6fza(r.

Which is larger, 1 Cv 4 mnczd+:seyb17txjq2;/ low; d8mb $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is notrl p8veinvj/: vc37; yzq mv.6 in thermal equilibrium with szqn;vvic3r7l8vj em/ . y 6p:vystem C, what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum ri- jbh ousb/(w+ubnr*8veted to a strip of iron. When heated, the strip will bend. Which metal will uwob(+ *b hj ns8rbu/-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 5 p 1govr ue+46uhor6oof 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 sim: .ut29( vt.uekvz0j )vb sjbeple thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. Tzb(t90)tseu:.eb vuj kvv.2j he 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 enia 6l(c4bjjkfbo 6b 34ds often have a section in the shape of a U. Whf44jj kb3o6cl(ibb a 6y?

A flat, uniform cylinder of lead floats in mercury at 07* namkh8yiw:(s yae, $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placr3kd9kmyj j/dh c*b55ed in a hot tub of water, the mercury initially descends a bit ankrh mj d/jydb35* k5c9d then rises. Explain.

A glass container may break if one parkpe*v58u)zxs;xf hj7 t of it is heated or cooled more rapidly than adjacent partsjvxp)s zx* k75h;e8fu. Explain.

The principal virtue of Pyrex glass is ttez/zgno)n .o9hk,q 99;lfqy hat its coefficient of linear expansion is much smaller than that for ordinary g ;e q99kgf q tn,loy9zn.ozh/)lass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock,gxlzv.8y)rb0p /zm 3l ;x+i pd accurate 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 badlg 5bas+51 vw(vq xi9tqy the can will not stand up. Wha vga+tixbwv 1(sqq595t has happened?

When a gas is rapidly compres zf4uk )b8a.atsed (say, by pushing down a piston), its temperature 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 ttzfka u4). b8ahe momentum of molecules when they strike the moving piston.

Will the buoyant force on an aluminum sphere submerged in watcw6 3 ey9qyb8ub fef/4er increase or decrease if the temperature is increased from w3yf6b4ce8bu f /9 qye20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kin)-j mwvcl5i f)etic theory and the relation between av)5mi)fv c-l jwerage kinetic energy and the absolute temperature.

Explain in words how Gay-Lussac’s law follows from kinfufr6 ((v-m pyjq we:8etic theory.

As you go higher in t q7qfny4iae qpqa6 pc/.:f/ 9mhe 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 hwe-i e-l u.h, u-7bzteave to leave the Earth and never return. The escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s sm-zheui-be l ,eu-w7. taller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room tempera2ub6o + 7zz w7 .zszpw0hxlu9lture. What can you infer about the molecular properzlo bux+29p .hu s7zzl0w76wzties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hot dry day at./kfr;pr(exk w5(rvfu bw;w2.z . hp s the same temperat;.e5fr(; zrw rb/ .fk. (puwkhpxsv2wure.

Is it possible to boil water at room temperatu 3bku49 g,w txqe/ud86zqgb.rre (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but bbae :2 .538:pdqr vtnrm cj(v0em/osthe humidity is different. Which is more dense, the dry air or(n2qm:3vpe0e .r s/vjcoa8m5b: db tr the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator ca8x +7nuvat6yk q m 8 9pbq,5qmye5th7qp of an overheated automobile engx e,btup7h y 75k 8n+9m5q6y8amqtvqqine.

Why does exhaled air appear as a little white cloud in the winter (Fig. 13–2/n r+s74cpiil8)?

  How many atoms are there in a 3.4-gram /iej(d( yv-oh8m.r khcopper penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the number7vm99lwm0;ygpc ad7mwfqfei 7a9 8 i; in a silver ring of the samwc pwfylm;fd79;m9 90 qa7mv8e ga7ii e mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsi2c tas gm5wx9g-a.ip2us scale?t2.g5-gw p2mc9 iaax s   $^{\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 ;z5f2wrcit8hir - c 0bj02t:as/ef eslowest temperatures recorded 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 d0w(;73ojrt kef)pmh column has length 11.82 cm at 0.j7)pe3dwk0fmr t (ho;0 $^{\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 slabs 12 m long (20 /e49/2 gou5v* amxu lnz0ctu ;mxr*ca$^{\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 wrought iron approxipteonc0 swm 6 d-0-)jumately 300 m tall. Estimate how much its height changes between July (average t)j0pmsn ue-o6dw 0t c-emperature 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 than the rivet :w zc;t+z/skzth174 qx3g nvi hole are often used and the rivet ;:qzns vi+tw zhk7xg4/ 13tc zis 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 4 48o2qgwyrxw960dzqm 6le * i3dv o nb;$^{\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. cv1aqeb e5 k/ lo0tl5vny7/ *cWhat will be its change in volume if it is heated from 3t l7b5 0 klan q1*oec5vcv/y/e0 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to e55o rjg9-grx ua8ag,the brim with 350.0 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 55.5iki5-+cwc- 0ky9pzvv)kj- qm 0 mL 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 to be placed i p 8(qd9)jo1lajg(t0 ihoefh,n 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 soo/qsl 5a2ykh7 it can expand in essentially one direction only, show that the effective coefficient of linear expansion is approximately eok2a57 /sql yhqual to the coefficient of volume expansion $\beta$.

(a) Show that the change in t t0zle(wfmz-l/ , ew4ao2u 0rmhe density $\rho$ 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 lenvmb2ljeq.lw - u ;z-/tgth l and width w has coefficient of linear exp;-lt z -wq mblj.2u/evansion $\alpha$ 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 isotrono)6 m/rjsh)k n9+cc0pd5alq1f4eun pic solid, $\beta$ = 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 *fdw s7+ v+lr6myebt6clock is made of brass and keeps perfect time at 17yf6 sbew +v6*r+tmd7l $^{\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 inside dia-b4tmv2o mm 9*)nkaz* c hofg;meter of 0.140 mm. The buln-;gob* f*v c)m94m hkt2zmaob has a volume 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 cylind(yyr pgx6/.jl3g b,lx rical wheel of radius 0.41 m is rotating about its axle on frictionless bearings with angul. r6xlpjg y/,bxl (yg3ar 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 1 kfg;gx9- rsqmuch stress is required to keep it at thi;1gfr-s gxk 9qs length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal stee;8: zd+r eszf+)uqc3 3xy maexl 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 20r4 o b0 nor51+ggf c2jyoveu9u86uuf; $^{\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 temperatures on the Kelvin sb ,-w7msc ze(mcale:
(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 sfz0 2cqj*wkn3 tr,s9on the Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are about h9)x/*s gi0/zxvx los 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 combust6swe ik r4qv2655wuyw ion engine, air at atmospheric pressure and a temperature of ab qy654ww rv 25eusik6wout 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 bm1 n ;m5(,sjcxae9)s; z ekatof oxygen at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogenwj :,w -kb j+r*g xodjvpep1:9 ($N_2$) 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 kg of nitrogen bo **t792 3) pdbstflq/, g6ozlde gyt($N_2$)
(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 at gxf;n9 v(z0cps/c q; ;og4biqkpq)m810.0$^{\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.)3 n.00o3xg gxgmxxnhdev 84 x7fhvy,0 kg of argon gas at 385 4 ,hgen8dx3vg0y 7fmx)3nx0.hov gx x K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg o4q8 eda+nfw b0f $O_2$ 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 br6ca 8 avj9/,ipod;adalloon, which makes it less dense than the air outside. Suppose the volume of a8r9vpdcadj 6;,i/a o 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,e 4cx+gmfc+( vqq5pl 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 atsyb3 os2l 6t bd,l0obez v:nb):ueg,, 18.0 $^{\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 escapes a child’s h8 ;3kqksfb, zt3(xlwoys7r ( tand 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 molecogb(z3 j+9:tni,srp nules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How many molec3fco fz;osr eiwu17z ,*+es9kules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (7 -c.8 mbpaeyoa) 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 s dcv(0q 8*pjimsda12zf7hll;ow:y 15.1$ \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 0tg b)7x8 rdugbx6;u vair are in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assuut7ggb 6v8d;rx0xub )me the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kine;ud*5lg;c ytio fpx-; tic energy of an oxygen molecule at STP?; tlg5u pi;;ycfx-o *d    $ \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 q68 hyy q jihg e+lg3t66*xc8oof the Sun at a temperaturhl oqj6 ghyit886+3c ex6 g*qye of about 6000 K.    m/s

  By what factor will the rms speed of gas molecules increase if the tempe2c ji qh-c :-ol+fdd1erature is inq lfcdh j--ico+d2:1ecreased 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 following speeds, given in unitshav b3 dcj8bxr8-xy(7wa:o7u of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms x8b h -7jxw83vayorcd7 ua:b( speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 2lx( rgnyc5p8tcu; l u;5 ne),n0.0 $^{\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 w b,yw3s pl 8lohl,(5qahile its volume is held constant, by what factor llq pyl,,as w58boh(3 does $v_{rms}$ change?   

Show that the rms speed of 2n9eizu i9)rvv b 0gypa12rz3 molecules 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 two gases at the same temperaj hx5am:f o;o5)jn2 *vxc;s iuture, the ratio of their rms speeds is equal to the inverse ratio of the square roots of th2 5mn ;jx 5 h;vuox:jisa*oc)feir molecular masses.

  What is the rms speed of nitrogl 04fx, g)baqhen 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 ofzq/o ilo28ve1h/ ivb* 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 d7 idz pyis1u qd/:f4-oistance between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of kr6lvx+u-gc9; -ocezr oci+s-*abi. an amino acid whose molecular mass is 89 u in a living cell at 37 cra x*6.s ovub-zc9gr+ei + ikcl -o-;$^{\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 of a gas can be w 8 1zjd1(ao9 vora6bcoritten 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 uraniu/ed3tppa6+w c m, $^{235}$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, i/9vno8phc+ udv/(,zi3 h6 v; py rsfdcn 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 2;dce6e(cnm h.01 atm and the temperature is (a) hece( m;2dcn6 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidi6d;e;xv(lulio5cyz o /l-k 1 bnl 78gxty is 50% on a day when the temperx/lb n;v eu5 l olkd6ylz8ig;cx1-7(oature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place wherelj 36torce,(q water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure a5b 1 sygcv rl:p:uz(u*e+ .bmpt a particular place in the mountains is 0.72 atm, estimate the temperature atrmz egp .vyu(1*sl5:c+pbb:u which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of wateri 6qvyro;; ce/omy (c; is 530 Pa and the relative hu;c;yy reioc/m(q 6o ;vmidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when3 m8wkmp:ksh4 the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the water imokxdan8 r17 0s boiling at a temperature of 120 rnx01domk8 7a$^{\circ} $ C? Assume no air escaped during the heating process, which started at 20 $^{\circ} $ C.    atm

  If the humidity in a room of vo69z) rj1x 6ncd vcgfpvkc-7u /lume 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 w(m9c,hdio- rpoint 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 molepa0wu.a8g .fggu49 0yssk(is cule (see Table 13–4) to diffuse a distance u4a .sg .wks00a98(gyup g isfof 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 interior through tiny tube0jc5zk-l vg f .)nim3zs callcm3 ngf iv.-05zz )lkjed 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 calibrated atddu((y6 zskk4 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 hab6/pt uar) w pahtn*82s 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 mtk-j0v9(z o tjuch error will be made in a recipe calling for 300 mL ot- j zv0(ktj9of 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 mai yj 5pc*7j7xwny balloons have been blown up, the gauge pressure has decreased to 5 aty i7j7jxc wp5*m. What fraction of the original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of lez8p ;dsvr1d b.ngth 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature i1d.zb;8 vrspds 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matterom/5.nrz.kj )h6 qbwvze bqg8 dcb 8/5 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 m,ylt/gl -6yz4a/ biq kdv*-l is about-dlvlmi *kb //g,yl64ytz q a- $10^{-12} N/m^2$ 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 w40lha.qklko5 hen 10 m below the surface, to what volume would his lungs expand if he quic k0l.45qkhol akly rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at a +vq2rjpciq5 / speed 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 matev5q+r jcp/qi2rials; 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 f0+rk3w)+n ) lj/fn/k*pkh*vzrajnmnrom 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 ofxnmhpk a p 8gh;g:-t+; 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 surface of the Earth, esticnyt)ge up()l8 yh i +2;y,harmate the tyhil 8 p)(y;ec,nr +t2h)gu yaotal number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitroyh lp71nka;0 j* v(qhbgen 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 ha z*z le- fqs:)3mec-yrs gauge pressure = 2000 psi (13,800le fe3 * )zzq:srm-c-y kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a b 3mm)cztscd)1g)d cs) owl 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 gasoline j m(cu*x 5th34igb*fu)d 61ba js/uck 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 +e hm8w 0uud b/9gbr.mthe Earth’s equator 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 at 2mv4v zlw7 7rxawf6i/g q:*lh/0$^{\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, adopth)tb:h1+qw9us) nvelvjgwo ; ;.jjr.ed 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 a pressure of q9l mzw/ 0nwgn 17mp5 1kut(lt195 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 Eartu4v02x5p 1ipl 8 -2/or4qjnruzndbcy h 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 li b48qhm n5l:fqd is suspended against gravity by tennis balls thrown vertically upward at i8mlbq fnh5q :4t. How 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-diameter (spherical) bubble of air o8slx z6b5 -cifrom a depth of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How large is the buxs -65obi8l czbble when it reaches the surface?    cm

  Calculate the total water vapor pressure iy 0 36iumvu8enhp+iprj 1j6g 0)fid g0n the air on the following two days: 6drg3 igf iij6unh80v 0j1)u0e+pmp y
(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 tz0s(dltnpovwg2; 4w *he density of iron at STP, and when it is a so*s0l ;gnz(pv4tod w2 wlid deep in the Earth where 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