Which has more atoms: 1 kg of iron or 1 kg of aluminum? See the periodic tabl6q*s9sy2e 59qe: j oz(lk)nmnxe.nxu e or Appendix B.2q 6q*5:yomsnx)xnuee 9s(zn9le.jk

Name several properties of materials that could be exploited to magr-rbw* wp-mt4r89 ksa (ps0wke a thermometw( pt-4k0 w*sw8r rabs-9 rmpger.

Which is larger, 1 C j+ylr l29w *js$^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with vns-ym v ahy6)hgv*1ym5t;/qsystem B, but B is not in thermal equilibrium with system C, what can you say about the temperatu16g*vv;m qyhym - vsy) a5n/thres of A, B, and C?

A flat bimetallic strip consists of alumid *dzh (:7 ,odiyllgj29:+g qzchp h-rnum riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the currh:(hi,:o yd dcgzd *pj7gq l2zh-9l+ve? [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 coefficie ri1 i;q/gbe5;y;yj fwnt 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 to cl+k nl.5)q od b*lrh0yontrol a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The). y+rkqll olbn *5d0h 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 t, t5f /n5ai.h ;u9q qan8kzbowhe ends often have a section in the shape ofqabt8 5ukf/q o., a9i5w n;hzn a U. Why?

A flat, uniform cylinder of leakhvi0zaxy,(zkkg/5yp*0pe vx m8t-w v)f(k0 d floats 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 thermometeiywl 8e(j 7-2vze8lf er is first placed in a hot tub of water, the mercury initially( 8 e8 fwyej-le7vzi2l descends a bit and then rises. Explain.

A glass container may break if one part of it iswt6vk2i /cy* k heated or cooled more rapidly than adjacent parts.i vyk6cwt2*/ k Explain.

The principal virtue of Pyrex glass is that its coefficient of linear expx d/k-n+6jm9c qbwd)fansion is much smaller than that for ordinary glass (Table 13+ bw6q nm-)dxdc 9kf/j–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accurate a3szrrjm,4 e3(: b n( epyak1pxt 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 itsgdr9, sn3ea 7 -iqgc*n bottom and top to bulge so badly the can will not staeg,nqi*a-gnrsd 3 7 c9nd up. What has happened?

When a gas is rapidly compressed (say, by pushing down a piston), its temperaturybjbf/5 ,7obbw v/;qhuls0l 4e increases. Whe/;w,l 7f/bsuovq 5bj0hb4l ybn 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 alumin: bd y1. krdrdn,2i,gy0tjdfbe6 h9 0xum sphere submerged in water increase or decrease if the 6 b9jg ,r, dddhe1xr2:knt.0 fyidy0b temperature is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory antitykp /.d i5: lk p(,cfqr/2ud the relation between average kinetic energy and the absoi fkrt2li. / uyp (dc5q:tpk,/lute temperature.

Explain in words how Gay-Lus)sjd cp. 8ncf2sac’s law follows from kinetic theory.

As you go higher in the Earth’s at o4/ 3i6ddy4e7;dm x/resjt1d od;rvfmosphere, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for them-f7 r;l/f+ 0kx gvcu/ bz2idp Earth refers to the minimum speed an object must have to leave the Earth and never return. T+kvd 72zlc/xfm;-fp b ru0/ ighe escape velocity for the Moon is about one-fifth what it is for the Earth due to the Moon’s smaller mass. Explain why the Moon has practically no atmosphere.

Alcohol evaporates more quickly than water at room temperature. What can you ixec1;4n d :sbbplar9/ nfer about the moledrl :bc;sp b1/a4xne9cular properties of one relative to the other?

Explain why a hot humid day is far more uncomfortable than a hox9bf65iw6niz h+b: 4-trqc ogt dry day at the same temperb6r-c6b4 9hzn+oigi:x5 q ft wature.

Is it possible to boilo (4lm6rv, acu7k(i,- enpa lx water at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the huxxbvrg6 4l 6cf+ p--) 35gx seleo7ehmmidity is different. Which is more dense, the dry air or the g 5 r4 gxlp)el7vx+xmceb6- 3fo eh-s6humid air at the same T? Explain.

Explain why it is dangerous to open f9e2s7l5w p,2w soxvbthe radiator cap of an overheated automobile evwwso7p9l bf 2s2e,5x ngine.

Why does exhaled air appear as a little wh8el(j4* ;iu0skh 2 cf.r.ddg-i vcjrkite cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper penny? eqatsi9,wl;kq9(k ,o   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the numkppo9xw rmw5d k;) 3/iber in a silver ring of the same)kd 3wm;wkrpp5ox/9 i mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What is this on the Celsius scal8a4 : yzv/+w3qbov ecle?8ab 3+coqvvzlw/:4 ey   $^{\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 temsx u2;2ibc1+h qam;nkperatures 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 column has length 11.8b*2 q9oww)e fj2 cm at 0.0 )*e2qbof wjw 9$^{\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 13ahpfx)7ig -s 9f2cz6y frhgt 962xk c2 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. svb5- hgq.pdux3 ulo+4c18 hj 13–29) is built of wrought iron approximately 300 m tall. Estimate how much its height changes between July (average temperature of 25°C) anj3+lxb4dhphuu.o1 -v5 qsc 8gd 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 hole are often userzxu :6f0fna 2;afn mq+og .f,1djy9t d and the rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a f,o9nm1da.qt62 :un0fx r;zj y +gf afhole 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 99)mrbvch: ff $^{\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 be0 jzowbk rb;*-xk2 k+h-qw;fc its change in volume if it i*0xwco2r;f+;hwq - k-kz kbjb s heated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the brimfdnokk4;p2u1r( m *jr 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 55.50 mL of waterhschn*smc6)7 u v.rclw3+s, q 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,co6jf/jsft2 of iron. At 20 $^{\circ} $ C, the diameter of the plug is 8.753 cm and that of the inside of the ring is 8.743 cm. They must both be brought to what common temperature in order to fit?    $^{\circ} $ C
(b) What if the plug were iron and the ring brass?    $^{\circ} $ C

If a fluid is contained in a long, narrow vessel so it can expand in essentij),j5lmffz :mwh2 x/1 28y 8z bsdhzqfally one direction only, show that the effective coefficient of lfzb2 21f ,wjhj8z8h 5lmfy) sx/ zmq:dinear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change in thev/ 8 a6hp(ggoy 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 length1spn zn 7g5uobh1t2 o9 l and width w has coefficient of linear expansion 9sng 71onuz21 t5phb o$\alpha$ 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 solidf 7taw9/qt mydx9g6,w , $\beta$ = 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+ujp4, 2kjv sx is made of brass and keeps perfect time at 17 uj,p+k4sxv j 2$^{\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 mcidjvfs7f 5lw 7*+y8diameter of 0.140 mm. The bulb has a volm+fd8 * vc5yi ljfs7w7ume 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 ofed -twzr-8m2rmytp+yd /9x 7g radius 0.41 m is rotating about its axle on frictionless bearings wdey rpmw+d9xy8 tmr7/2g-t -zith 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 lenizz -w8/s jwqlz)pa ;uh1-ltz: y7 hz(gth when at 15°C. How much stress is required to k(zwzz 1w /ul ht:zp z l)is-qha;8-yj7eep it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel;eke6th :wa/s 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 134m 3 psbqqyc*d*etu 0 20m*ul q56yv;cj.122 cm at 20$^{\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 scok/ )wix z0fi+ale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on the Fahrenheit snk13yq-qwk(7 hqh/iscale?    $^{\circ} $ F

  Typical temperatures in the interior of the Earth and Sun are aboue+imu +r-/ rnzlm 4p23vwwv8wt 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 tem.l/yv uc0m8ro perature of a0 uc8 ./rmlovybout 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 idealryf:s07 -+g r6zv1omncc5 eho gas law.    kg/$m^3$

  A storage tank contains 21(jg e j6ecj1c(b a2*mq.6 kg of 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 contains 18.5 kg of nitrogen (ts9u k/ch 74ipiy k3mlfr)) u/$N_2$)
(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 heliunjnqgu ; 9gv igu;k/)1m 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 fc-+c.d4ssyjil v)0 c*hfqlc*1 l ,obcontainer holding 105.0 kg of argon gas at fyl v sc,*bl1 scfc.ol0 ch*)diqj +-4385 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kg o9n :mjy1fx* nof $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air inside the balloo kfwl/m1 gmd08n, which makes it less dense than the air outside. mwk1g/8f0mdl 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 ai) /sybre2eg.kfuj(f)l57idv r 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 at3qd7mdjg0: dv 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 ballool;cb+ dx ne+o cwi-,w3n escapes a child’s hand at sea level and 20.0 $^{\circ} $ C. When it reaches an altitude of 3000 m, where the temperature is 5.0 $^{\circ} $ C and the pressure is only 0.70 atm, how will its volume compare to that at sea level?    times the original volume

  Calculate the number oftji(t,uzoh:38u l/p;xi 9 ocrcht, w) molecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L?2lf/ n 1mf t9fs,vclkz/ 4o;uu How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number o (z ,y(hgrcieaov/qp o/k,7n -f (a) moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume7e sc nh6la qs 6a76.ubj;*dbd 5.1$ \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 ofu:2rw jv,,m qi air are in each 2.0-L breath you inhale that were also in the last breath Galileo took. [Hint: Assume the atmosphereu, :, qrmivw2j is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinetic energy of an oxygen mol: a +zzlvcz5;decule at STPa vzcl5+zz;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 spe*pxn bw,l 8 jf3)1.mo)sg.aksz s+rfg ed of helium atoms near the surface of the Sun at a temperature of about 6000 K. gsm3)wpak.8r bsfs lzf*+g )n.1,xo j    m/s

  By what factor will the rms )th7an5 (ug*ae ah;st) ;j,kt tdr:dqspeed of gas molecules increase if the temperature is increasn5;tt ddjaq ug)7:(k*athr e h; a),sted 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 ;7-*gld- gikieddmwbswy 3z .,ld *d4;7rxmgin units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calg.bsw7 **3kir; yg;edxwdm, d-i7zm -gl 4ddlculate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 9 1 ggyezziq4rn-; nf320.0 $^{\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 held constant, by whefq:kqg k rg65j xkc95g,**ce at faq*g:frkc jg*,x ckqk 5 ge659ector does $v_{rms}$ change?   

Show that the rms speew3(7ep f ys3sed of 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 gaseskf.l jac1e q; xo21b;n at the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of their moleculare 1n ;2a1;obj .fcxklq masses.

  What is the rms speed of nitrogen molecules contained in an 8.8opzm98q (py t e (x,jsqm;+sg5$-m^3$ 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 atfi5rdu*o- op (v61:ptlx ar*ks w4l:s 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 (uq tt7y6w1otfn ) d.7of+odf between nitrogen molecules at STP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mass is 89 q ko*d(1ee++h - qkfspu in a living cell at 37 +kq + o-ee*qhk(p1sdf $^{\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 cv2+ bo)(uz.r.fyuoe nan 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 7x0wqnyhh; v63f 3c dluranium, $^{235}$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 pr6hmo enkpewh74:8f;owi( 0y sessure, 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 an 9xw58r/ge*i6 w4dj2a-. mmnlowwi dld the temperature is (a) -ow m8*in .gww /j5 4lrad29dxwel6mi90 $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew poina*y ,:hp5izn bt (approximately) if the humidity is 50% on a day when the temperaturezn:*y,5 ahipb is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressixy1.41 chpenn it1b1:e2uh bure at a place where water boils at 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the moun*pu9vac m0noc/ + bk2ztains is 0.72 atm, estimate the temperat ccvup/92+azk o 0m*nbure at which water boils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when the partial pressure of water is g(s*+xfmo 3fr* z kj/h uv:yd:99tmnc530 Pa and: /fjcogmhz:(tfv9d mx r +u9s*3k*y n the relative humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day whxqn6 9xadg:cp-m 7dn1en the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the wate4gbtyow .7yt; r is boiling ywt by4 t.o;g7at 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 o7.p / fu3g row,owlsle)yt c l4.51drrf 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 poinzo el) de0/ 07u)i;61iy 2 uyi uzjehk7acaxy9t 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 r (7fcf2wq1. hv:dusdc.0rmx glycine molecule (see Table 13–4) to diffuse a disr.cwq:0d1fhmuf (crdxsv. 2 7tance of 15 $\mu m$ in water at 20$^{\circ} $ C if its concentration varies over that distance from 1 mol/$m^3$ to 0.4 mol/$m^3$ Compare this “speed” to its rms (thermal) speed. The molecular mass of glycine is about 75 u. t $\approx$    s ([color=rgba(0, 0, 0, 0.85)]Round to one decimal places) $v_{diffuse}$    $ \times10^{ -5}$ m/s
$v_{rms}$    m/s

  Oxygen diffuses from the surface of insects to the interior through tiny t-:a o9ybu (nwzubes called tracheae. An average trachea is about 2 mm long and has cross-sectionalyn-uzb:a w(o9 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 8 n6n:opub7/ g 3mq6 domdrac4measure 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 calibnn,m2 wf;p. zyrated 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/oi: ilzbawbld qlz093vsf8m-d)c vf8 r 02o0 much error will be made in a recipe calling w0d /v9zodfaflclim 32ors: )0b0v 8z lq-ib8for 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 cylindqzsyqj(8+g* u7 (/nxsc si l/mer is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in tu7z/giy8slqs*s(cq ( xn m+j/he cylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, width 3.1 ugfvkl. 9 1ul,wx9/p9j wrhl;m, and height 2.5 m. Assume the u w ;ukf l19l,vjp9w h/gl.9rxtemperature is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about one atom p9qak) a4j(ykker $cm^3$ 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*s*iu ot20)hfva6ej:o 9nthx the best available vacuum techniques is aboj)te th2*soin6uxao* : h0vf9ut $10^{-12} N/m^2$ 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 9j -zqc8e e8o c,fwje ggk:7w9below the surface, to what volume would his lungs expand if he quickly,cg 8wjee o-fe:gwj897q kz9c rose to the surface? Is this advisable?    L

  A space vehicle returning from the Moo /j zl;c)p yxfrn,;u6on enters Earth’s atmosphere at a 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 materials; indeed, part of it does vaporize, and this is seen as a brigh/uox6c,jyzr; pf )n;lt blaze upon reentry.)    K

  The temperature of an il /ll /8-g e4uqz:bw+zcuc o,gdeal 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 of 74ju /i n(mzgx+70m$^2$ (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 valueg.fdbu * bb/zbl7 q7r1 of atmospheric pressure at the surface of the Earth, estimate /br7 qf1lb7.dgb zu*b the total number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules7(wr6 ,mxoyqcnui1) w 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 w 7)(syc);dpj 2*ht pn ux/qx.nhg cs0used in a hospital has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at at u;)c/0(ywx*h27. hstg dqspp)nnj xcmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of liquid mercury at 0 n c- adie 4mp-2ozuw;-:min6m fjy.u0$^{\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 gasoliq+2dchw*:q g, /irbasne 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 arlepj e*gwi) )tf5 (y9hound 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 tro hj 4d:9ue) u(qcng4ru+f9onto 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, adoptppb/iv91;j mq 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 195 atm 5dpb5/;; s k-h d pcaiqyego81at 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 fro2 um+k2/b mmgf fq*)yrm the 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 tennis buopb-)4y7zd , l -czfoalls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elasy-uzz ,l)bp ocd7of -4tically, 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 (s;slk; s:agbrc2 ps7o 2t;omb2 pherical) 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 surfa pg22:tr k 2cslmoas;;o7b;bs ce?    cm

  Calculate the total water vapor ukcu 24qsij/1pressure in the air on the following two days: u/ 2sui q1j4ck
(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 irb) fs*)jr-x gmon at STP, and when it is a solid deep in the xm)g*jr)fs b-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 

(a) Use the ideal gas law q/pmdox 33nm3bzt 05gkv6s. u to show that, for an ideal gas at constant pressure, the coefficiebvo k3qpsmgnu50.mt36z d3/ xnt of volume expansion is equal to $\beta$ = 1/T where T is the temperature in kelvins. Compare to Table 13–1 for gases at T = 293K (b) Show that the bulk modulus (Section 9–5) for an ideal gas held at constant temperature is B = P where P is the pressure.

  In humid climates, people const1nif+rx(ea0dtf:2 7 sf goi5 kantly dehumidify their cellars to prevent rot and mildew. If the c5e + 0:fafkio n1gsd2if7(tx rellar 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