Which has more atoms: 1 kg of iron or 1 kg of aluminum? See x 3fni ;x41yhxthe periodic table or Appendix B.x;fh134 xniyx

Name several propert od 6o4qo1x5nbies of materials that could be exploited to make a thermometer.45x1nodq 6obo

Which is larger, 1 C xw vw 9/fngmte-7:j;w$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in the8s)gr sg3 a0 seu.u)9g hfd(h 9dl/aezrmal equilibrium with system C, what can you say about the temperatures of A, B, 9guh l))rze g us hgs0.3fed8a /a9(dsand C?

A flat bimetallic strip consists of aluminum riveted to a str0jni0 no.ntpxo1+ 5t nip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint: See Tab nx5o 0t.np+tjn1 no0ile 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 coefficie,s2oho0 y/cb unt 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 simpa,pm/i3;u fw wle thermostat used to control a furnace (or other heating or cooli ip/3; a,umfwwng 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 often have a sectio*h-7; ((w year dlsoe ,uqr(vvn in the shape of a U. Why rvyowadee(7 sr(,vul- q;(h*?

A flat, uniform cylinder of lead floats in mercury at a:jfld ),3n ulj (hboh:j5 uw00 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermomefl3v: -vqx -knrw y 1(6i)lkenw 7(eg;rm6jttter is first placed in a hot tub of water, the mercury initially descends a;y 76v qjr(1 ) et6(e-3n llwnm-k:kigwvxtfr bit and then rises. Explain.

A glass container may break if one part*u u7j khq+yqmlc+6 l5 of it is heated or cooled more rapidly than adjacent parh+yk+qu 67 *cmlulj 5qts. Explain.

The principal virtue of Pyrex glass is tha-)que)a: nd .b4j1qvk2d vmb nt its coefficient of linear expansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives rise to the increased )dnb.em1j qun4)v kv a-2:dqb heat resistance of Pyrex.

Will a grandfather clock, accu9jgzttt vk-l2gm 8p.7rate 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 anduow1bl 52g-rx top to bulge so badly the can will not stand up. What has haxuw52r 1o- gblppened?

When a gas is rapidly compressed (say, by pushing down a piston), its temperadgc,168b m ngcture increases. Whe,cm8gn 6g 1cbdn 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 onmu:zeofisi. 1(a7al - an aluminum sphere submerged in water increase or decrease if the teo-imlz1 sia:.f (u7a emperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charf3rxug-ca(n1 les’s law follows from kinetic theory and the relation between average kinetic energy and the ab (fgrn1xau3c- solute temperature.

Explain in words how Gay-Lussac’syovc-f 94p cko 4x(sc.yklxoy2x*/qxns 5*4q law follows from kinetic theory.

As you go higher in the Earth’s atmosphere, the ratio o4hncy zvk p (p9b,p*c0pny88pf $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum speedebvg -a fqwec2o3g6;9 an object must have 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 smallw q6gbe gof2ac;- ve93er mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. What can you+ +4yzcu pnl*t5eaj )u infer about the molecular properties of one relative to the uln)a+yp* jct54uez+other?

Explain why a hot humid day is far more uncomfo+4n2* zkcdeer rtable than a hot dry day at the same tced4rnez*2 +kemperature.

Is it possible to boil tnh2hycwap +3i/ x5 0xwater at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days whed*dq0vq q oi+:n the air temperature is the same but the humidity is different. Which is more dense, the dry air or the humid air at the*:d0 qqiqv +do same T? Explain.

Explain why it is dangerous to open the radiator cap of an ovee)j+uo- wj5doplpr kl4zv,+3)vp g; urheated automobile en;v pz5k+d,p 4j)we- juv +u3or)lploggine.

Why does exhaled air appear as a little white clou(k csu n9o gmd(. 7x.gd0ezp2ywq0 4o;lywo(yd in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram coppeh4* vluxmq4p) r penny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ri.i s 2g) u97ob3xgflseo2at,eng compare to the number in a silver ring of th au7leb,xosggots e.f 293i)2e same mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. dncmkm5 7 846jb.l brvWhat is this on the Celsius scale? 4bcjb r657dlv8mmk.n    $^{\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 recqwhgvn ;qo83s+ cb3b)orded 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, teh7 gqn :u ;bq*0sdt,nhe alcohol column has length 11.82 cm at 0.* q sbt: ;n0ndueqg,7h0 $^{\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 3p52ke go f)eo$^{\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 approximatelym73 rd5.ti x3zx/sbvr 300 m tall. Estimate how much its height changes between July (vsr3m.3b triz 7/5x xdaverage 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 kckvg, gs*5w;.mp 9i4)gdj magz5,jw , rivets that are larger than the rivet hole are often used and the rivet is coojg5zm;v iwpa g5,m s4c jdg)kw9g k*.,led (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 e cmgoh;5s./v $^{\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 zwh; c 7y* *hdkz+l-vw5vh4jz in volume if it is h-h*j4l dzh +5*zvhkwcvy ;7wz eated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brim with 350.0 mL of water okj 3pmn3e556qq5madh7o+i uat 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 ew 26s yw0l u1pay:0cb55.50 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 placm4fuz5:xf2dwc.dd kyel58 4xed 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 ve p-wrk-jl6p:kmzu10 e ssel so it can expand in essentially one direction only, pe-m-:01w6rjuzkpkl show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the changehwihbw): 728q6t iq atcnm5:gpflr : 3 in the 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 length l and wi k2f zjo(6mp:n/f42,y lurjqqdth w has coefficient of linear expansion n,f:2rj(/2m6f4oklqq j uy pz$\alpha$ 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 soliou)hp mg*m k3/)paj7pd, $\beta$ = 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 grab 9hjltp6l28 tndfather clock is made of brass and keeps perfect time at 17b j2p8tl 9hlt6 $^{\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 hajh raaf48dggq9 45 *iu:d06 wmhepk(ks an inside diameter of 0.140 mm. The bupiuegha(9 a4j6rdwqh f4k* 5 mgkd8 0:lb 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 cylindrical wheel of rad88tav96 4t1,roab dwdoqho 9j ius 0.41 m is rotating about its axle on frictionless bearings jva8q,8 orhd1d4o9a tb ot6 9wwith 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 strzgs6o(v8sjqmdbmrxl 56fq b 0j 6: 9d1ess is required to keep ilgm1 dov:rdj 8b666fqj zxq 950m(ssbt at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steelq lef6qe qgu z(;:r-7l 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 k6/u; xsexk 0v20$^{\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 tw8ako xt*gr h1mnn4-j3 , o4oqemperatures 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 Fahroet4 rkzt ,v9-enheit scale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun arf)qjb /qc8n3bl0 .eew:zr i2l 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 a temmd+uku5- .e2b hj5zlb perature ozbbml5 +.ku5j deh u-2f about 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 gas law. uo1k4u; dlrj2 )gp*qx    kg/$m^3$

  A storage tank contains 21.6 kg of nit 840dpaq0fubo rogen ($N_2$) 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 on0r,yg hyeztlk1,n; + j:dj0.5 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( jshwsyu 1.-3i/tqt r gas 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 kgcm 8jrlxh9zj2 q3;zl.5 -frmi of argon gas at 385 K?lcrq253hrzz .j9m8;mlf i-jx   $ \times10^{ 8}$Pa

  A tank contains 26.0 k fk./r. 1 5ppdala8vqdg 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 bjt,t. xr hvo20uoyant lift by heating the air inside the balloon, which makes it less dense than the air outsj2x,r.oh0vt tide. 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 withn pjhu;gr (1r5 air 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 ,e7)cmrz fvp7 $^{\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 ch abxxohg*x,9m3 6s j.oild’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 moleculesy yj fa;60a wva,of5c/ / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there:. eiax5 n53cfxv(opp in 1.000 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number of (a) moles, busd4i.aob r+q1 8xk)- kn bc8   $ \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 533c cz.i8,f hgkajj3a.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 im 9a 9d :re2--uchxugbreath you inhale that were also in the last breath Galileo took99rumx2e -hudai- : gc. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen m/stzze+*fc ie r 19x *rsy9y.lolecule at STPy*zs99e / zfryx* l1 secrt+.i?    $ \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 the Sun at a tempera39h erpa39ipo3 cj8wwture po pa38cw r9e9w3 jhi3of about 6000 K.    m/s

  By what factor will the rms speeddv:; m zs/9h+ifcfrm4)q:6reo x/el u of gas molecules increase if the temperature is i4lfr + m:veqmer;zxoh/)6c /:u9s ifdncreased 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 units o2zwwb,9*4cr bv-pm8 n. x astsf km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate the rms speed.b*.wtpcmx2v na9r,s bw8sz 4- $v_{rms}$ =    km/s

  The rms speed of molecules in a ga ba/37hs2qf3pr- up 1wy,-k6gthrf neqkk 7:os 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 ef6 w l4qdbs+x:sf z:+is held constant, by what factorb +4w sz6d:se:fxq+fl does $v_{rms}$ change?   

Show that the rms speed of molecule, svcdqirf1: 7)zuu)o gb. br8s 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 tempuwn :uwyu l:,v1kwod6xyrh)-d4c :q 49vsg m3 erature, the ratio of their rms speeds is equal to the il q:wd -s3 mw )x4ug:dyyvcu9n6u:41okvr wh,nverse ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contained in a33 ryi y)r.0,qn9*th nfrted- tulu3vn 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 an oxygen molecule y ficyqab3)34 4hk5jaat 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 betwee-7 y6dmxn6bgk f:ylz6n nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an aminif+f cfw/yr ((o acid whose molecular mass is 89 u in a living ceyirf( fcw/f+( ll 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 pressurexr2j+0e1zsm325lez 1r om p jb 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 urcoy:7wk8v3* lcxrjssbv60w 2zw fcbgm ( 3q1 .anium, $^{235}$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 prezq0088j0wnf oxu 3v bnssure, in 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 and the temperature is (a6 cc*4 ee1vk)s)wy rli) *ce6lv4 1yr )ekcws)i 90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humid-jpc/:notsb0;ct6ht7 j+nxe ity is 50% on a day when the tempe +njseb7;:htj/tcn -co6p0txrature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place whek7)+q z- ,+m; g:lwrrrsqi pwhre water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains 2 ltcg:ueqj6x1e+w u, is 0.72 atm, estimate the temperature g wl:ux2 6je t,1cq+euat which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is 530 Pa 4pakd .tyc6rkm 1,p mfs bp.6.and the y,k.t1 p6m4parp.fd sbk.6m crelative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature i)awi;h mr0cgx548sb ds 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure insid/;xxdt b (i.oje a pressure cooker if the water is boiling at a td( xjo.;bix /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 of vockp jf7ioz k869a:,oilume 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 of o( /q*nn/tmi7. knbx t5 $^{\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 molyl,)m*zc0;cw,o g z isecule (see Table 13–4) to diffuse a distance of 15*yl;cc m0sg, )iz ,wzo $\mu m$ 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 tinypmz.q91 ij-5tl.1r tlpy*kbj tubes called tracheae. An average trachea is about bz*m5tql itrj- 1k..9 pl 1ypj2 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 measuem bk5n72it8hdc e: ;+ ,ayngjre 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 precise steel tape measure has been calibrat w7:a jrho; qax5mlk;- r.g1mied 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 temperatux)ro2;td, * 5cuy pretre. How much error will be made in a recipe calling for 300 mL of cr)t*p5o u,te xdy2; rcool 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 cylindeodfq,x/*2g p pr is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of txgf/p *qp,2 odhe original gas remains in the cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, jecsh+em*y (53bqb1 hwidth 3.1 m, and height 2.5 m. Assume tm eshb 1b+j(ehyc3* 5qhe 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 v4 )ls.;qmqk0q gan1 wone 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 isjl687w cq9 yod about od6j89y qlcw7 $10^{-12} N/m^2$ 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 2 hiba,b gt:x;10 m below the surface, to whb,ga2 : tbih;xat volume 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 speed ofl raq ,oif7 yy jqs0xo)wt *.*pj+v3+h about 40,000 km/h Molecules (assume ni7rsp,xf+3+ jvy liqo*. aqojt*yh0 )wtrogen) 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 does vaporize, and this is seen as a bright blaze upon reentry.)    K

  The temperature of an ideal gas is increased z;) eg )1za8lns4cgpqfrom 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 faavk) i*) e):qmu8 qj770m$^2$ (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 prel n4bx4wt,zl 4ssure at the surface of the Earth, estimate the total number of air molecules in the Earth’s atmospblzxwl44 tn ,4here.    $ \times10^{44 }$ molecules

  What is the rms speed of rv zand.:jf9pg2s12q nitrogen 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 use0n8y j)y*nex qd in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How 8 0ynx*j)eqy nlong 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 bowl of liquid 53xkx- za 5ekgmercury 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 *,uf 0xy3fpm+) pa ywsat 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 aroundo2pm wg qpa7.3 the 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 onj ryp- 1 k3ft(hv7syh4xhmq42 to 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 standard, adopted in xyab9rtgb4x- i0n f m+dqj /7)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 ch+mdf2d77pl6w m pz8br3+nvtrarged, 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 t v4- +lc5jskufhe Earth 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 tennis4wcre,cjm fagv+m+5 q3k2 9 wu balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass of 0.060 kg and are thrownqm+92,wewg5f3ma + 4 j cvrkcu at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter ( cj9r-e dcy98fspherical) 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 a perfect gas. How large is the bubble when it reaches the surfarj-ccy 9fe9d8ce?    cm

  Calculate the total water vapor pressure in the air on thw)(gysc 2vju 94zfx-hbu: v4 ge following two days: g)4:x2( vbu u9wzfch sj-4gvy
(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 inylb7nn )k7) cc the density of iron at STP, and when it is a solid deep in the Earth where the temperature is kncc77y lbn))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 thatx crl 1,:x )ckv.ra :d1 0lsylt:rxf*i, for an ideal gas at constant pressure, the coefficient of volume expansion is equ.dl ycrr f1c:lrx :x0,ika* x1v)tsl:al 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 prx,lwq,m,0vyvkop8 kt * 9ro)l:c 9xmbevent rot and mild lcmr,w,,v80k9okxq*my) t:v 9 oxlp bew. If the cellar in 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