Which has more atoms: 1 kg of iro- xgd,i/v /pf/m c*9lzwz ol7un or 1 kg of aluminum? See the periodic table or Appendix/im/l,-lz *ofgw7 pc9dvzux/ B.

Name several properties of materials that could be exploitedocb4u(2zf3i ea )zawpni ;;s2 to make a thermometer. s2n 4 3c;wz(iu;zo)2paifeb a

Which is larger, 1 Ce w2oz:osqzvo 1q-1q ) $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, but B is not in therm:oxv*we ibu 5:al equilibrium with system C, what can you say about the temperat::bu5wo xie v*ures of A, B, and C?

A flat bimetallic strip consists of aluminum riveted to a stritbqp(.d2lbx .xqd (6wp of iron. When heated, the strip will benbdqwb x.(p2 6t (lxqd.d. Which metal will be on the outside of the curve? [Hint: See Table 13–1.] Why?

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

The units for the coefficient of le:8)xbe6q jm dinear 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 diagram4e yn6+ cbq6fu ;2;cov(blhqr of a simple thermostat used to control a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch46 2o;c+; uefbyr 6(vhb ncqql 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 fh0 pm1n 6p6ehbixed at the ends often have a section in the shape of a be6p01m n6hph U. Why?

A flat, uniform cylindeg50ysb:xh1 1t:gdpq fr of lead 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 thermometecmxzhv vc b5c/t2;dj 9)v0i w-r is first placed in a hot tub of water, the mervxitb5c-hz2cjc9m ;vd w0 / v)cury initially descends a bit and then rises. Explain.

A glass container may break if one part of it is heated or coole/yc*3;1cj ,a8v7ikogqarix:o s7 h lyd more rapidly than a hy8y:c sxci7o*k1/3i rg ; j,7lvaaqodjacent parts. Explain.

The principal virtue of Pyrex glass is that its coefficient of linear e5atejpzjpzyml - mvj96,ost0 7 .d6y7xpansion is much smaller than that for ordinary glass (Table 13–1). Explain why this gives-0jd7,z7lz j69a jp5 yev.6o pmtsmyt rise to the increased heat resistance of Pyrex.

Will a grandfather clock, acc0t8a o*8uhw: (tv q)m9mpx dmdurate 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 qv ya5)opu-vgx(6 .kbbottom and top to bulge so badly the can will not stand up. Wh -vag.xq(uyk5bvop6)at has happened?

When a gas is rapidly compressed (say,b1v/m 4e0h dt8zz7 vmf by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using mt/8vv7ez dzf mh104bthe kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving piston.

Will the buoyant forcefg-8lf ff3 n 7w 19lii1mo+zoe on an aluminum sphere submerged in water increase or decrease if the temperature l fw1l+i-7o3e1 omzg9nfiff 8is increased from 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charles’s law follows from kinetic theory and the relati am oq17w,tvfy k;d/m.on between average kinetic energy and the absolute temperaturm /dt.7akwo,f;vmq1 ye.

Explain in words how Gay-Lusacjw i+yel,2xj,- ej 2e)wpohn9vd6 7sac’s law follows from kinetic theory.

As you go higher in the Earth’s atmospherec-aq z+ z8h,l / ,p*c:dvpulax, the ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimf lj6:w *lrn9wum speed an object must have to leave the Earth and never return. The escape vef6jwwl9r l:n *locity 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 yow 83d/n0mfhml sz udw1:0z+zo u infer about the molecular properties of one relh/mzsol 1w wmz8 30nzdd0+:uf ative to the other?

Explain why a hot humid day is far t a+7a9+:cwe a osito*more uncomfortable than a hot dry day at the same temat+ sa:oa7* oewi+9tcperature.

Is it possible to boil w:g; i zppuo6e ;-ju.lwater at room temperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the huymjvfo 2y++ )umidity is different. Which is 2+ yjum)ovf+y more dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerou0jhw6ci3dx2wz e.z w0s to open the radiator cap of an overheated automobile ch.w02 exzdj 630iww zengine.

Why does exhaled air appear as a little white cloue+bqbpn74f v7t6c ;n1/ esn dwd in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper penn9i d6km5 ia ve(4n-acj: cq+hfy?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26riqjp,g-i t69.5-gram gold ring compare to the number in a silver ring of the same ma j-g9 piqri,t6ss?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. What 7o*i fg+eiq.vis this on the Celsius scale?fo g i.+ieq*7v   $^{\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 recorded are 134cik/-xv n) ot6 $^{\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 11.82 cm atk5e nyr y;)a7rj z3-qp 0.0nyp 3-jr)yz k;7qa 5er $^{\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 builttpo6 fl**zo- w of slabs 12 m long (20 $^{\circ} $ C). How wide should the expansion cracks between the slabs be (at 20 $^{\circ} $ C) to prevent buckling if the range of temperature is -30 $^{\circ} $ C to +50 $^{\circ} $ C?    m

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

  The Eiffel Tower (Fig. 13–2mos-in(s;f 5d ugst8) 9) is built of wrought iron approximately 300 m tall. Estimate how much its height changes betweu dg5siso-nft)(;s 8men July (average temperature of 25°C) and January (average temperature of 2 $^{\circ} $ C). Ignore the angles of the iron beams, and treat the tower as a vertical beam.    m

  To make a secure fit, 1-shzvq:md;y1 i( b 2wkik4hzrivets that are larger than the rivet hole are often used and the rivet is coole: mb iwk41z2div-(zy 1s;h hqkd (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 at0lezhx-rb ;omz6xt+ * 4 $^{\circ} $ C is $ 1\times10^{3 }kg/m^3$ What is water’s density at 94 $^{\circ} $ C?    kg/$m^3$

  A quartz sphere is 8.75 cm in diameter. What will be its change in volume if (c hhiehna-2d9snnfd 02qu85 it is f2c hhn5sqdnnhd89u0(i2ea- heated 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 w9(+apu f 8zg j8kz0xqgs8vv ;iater 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 -4hig n ep ja5p84m5jx55.50 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 placed in a ring made of iron. At 20 ng;fo *;ypb5 b$^{\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 s,n;io.hd 9n icb;/xd jo it can expand in essentially one direction only, show d,bx.;h/ n;9c djn ioithat the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change inwwf/l p)o;i )f 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 width w has coefficient of linear( )22erssn olqq32txc expansion2 ocxsel23t) rq 2snq( $\alpha$ 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 solid .tf9 ,b8rnf;vfdp -hq, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfather clock is made of brasw +c79zf30kg * 1 4)9q lwfq;zwwihoubaj:xm zs and keeps perfect time at 1 7z9wqw4;b+k ljz z:*xiohwg 3wa 0uf1fqm9c)7 $^{\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 diameter of 0.140 mm.30 iqr0w ms ,pbez,df0 The bulb has a volume of bzrqs00 epi3fw,, d0m 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 ra++phv-1cqjhf s -f;nt dius 0.41 m is rotating about its f+p -sct n-qhv;+1hjf axle on frictionless bearings with angular velocity $\omega$ = 32.8 rad/s If its temperature is now raised from 20.0 $^{\circ} $ C to 75.0 $^{\circ} $ C, what is the fractional change in $\omega$?   

  An aluminum bar has the desirewc5 hf9r pl3w3mbn0f 6d length when at 15°C. How much stress is required to kc 03fwlhwm 6nb53f9r peep it at this length if the temperature increases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of cross-sect91 ,o*xckjeyyional 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 134.1,ej+ae3m z-nuwtc5 3c 22 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 te5;( jt hemncs-c/,izly2 f9a emperatures 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 Fahrenheio2mazj09i6 xg6e(pk kt scale?    $^{\circ} $ F

  Typical temperatures in the2lte wud3y -peo::lk( interior of the Earth and Sun are 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 engibw+p zt 3l;e.qne, air at atmospheric pressure and a temperature of abzblpq; t+3.w eout 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 ara 4,.zxlq; rot STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg 4-a+fsqb.kzltxrwbi. 83 *chof 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 containhi ;mvp (7 a z0rgahw(k/ms,/xs 18.5 kg of nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas o p6.aknyv-l5 is at 10.0$^{\circ} $C and a gauge pressure of 0.350 atm, (a) calculate the volume of the helium gas under these conditions.    $m^3$
(b) Calculate the temperature if the gas is compressed to precisely half the volume at a gauge pressure of 1.00 atm.    $^{\circ} $ C

  What is the pressure inside a 35.0-L container holding 105.0 kg of k+edb4i wyb-j2ftq :0hw,a) vargon gas at 385 Kh:e+d ,y0w)b bfw4t jki-av2q?   $ \times10^{ 8}$Pa

  A tank contains 26.0og4i;h rifirf4a3xql4) s 8( c kg of $O_2$ gas at a gauge pressure of 8.70 atm. If the oxygen is replaced by helium, how many kilograms of the latter will be needed to produce a gauge pressure of 7.00 atm?    kg He

  A hot-air balloon achieves its buoyant lift by heating the air inside the bx*5yc4wx*ikk) /e bqkd .4otkalloon, which makes it less d*qdokx.4k/bwx e)ktkc5*yi 4ense than the air outside. Suppose the volume of a balloon is 1800 $m^3$ and the required lift is 2700 N (rough estimate of the weight of the equipment and passenger). Calculate the temperature of the air inside the balloon which will produce the required lift. Assume that the outside air temperature is 0 $^{\circ} $ C and that air is an ideal gas under these conditions. What factors limit the maximum altitude attainable by this method for a given load? (Neglect variables like wind.) $\approx$    $^{\circ} $ C(Round to the nearest integer)

  A tire is filled with air at 15 t9),iakzhj q 1$^{\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 1/8e)/uz0 q a f2 eztikh80ckug8.0 $^{\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 cho9 zn*.o-/h4jxhk9iv pw.slo ild’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 mod i*q5d erwqsqm) s38ry89yz,lecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.0-c)l:idm a 7d(- qxm0hgy wv5y00 L? How many molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number ojgt* :z3jnsey1xhv;: 6fwe x 8f (a) moles,    $ \times10^{22 }$ moles and (b) molecules of water in all the Earth’s oceans. Assume water covers 75% of the Earth to an average depth of 3 km. $\approx$    $ \times10^{46 }$ molecules

  A cubic box of volume 5.1gv6* y e6hqlxd:qlb.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 8xu36 xub,mo gof air are in each 2.0-L breath you inhale that were also in the last breabmxo 6u, 8g3xuth Galileo took. [Hint: Assume the atmosphere is about 10 km high and of constant density.]   $\frac{molecules}{breath}$

  (a) What is the average translational kinakfkd2+md4 n) etic energy of an oxygen molecule at STP? d df2nmk+)4ka   $ \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 o0 .w/b5diczy the Sun at a temperac0o w z/b5idy.ture of about 6000 K.    m/s

  By what factor will the ry6 :ltr 4u7ym0jcz qw:ms speed of gas molecules increase if the temperature is in76 m::0 utzjcrq4 wlyycreased 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 followio2 q423p +qhd4a(vkjf e1fqmmng speeds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculhm2mdo q evfjqa+1 qf4342k p(ate the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a 3pt6wual3v(- 2 zrt3 rhm .timgas 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 itsn18 ;qy4 gxmxp volume is held constant, by what factor do4y1gqnp ;xmx8es $v_{rms}$ change?   

Show that the rms speed of molecules in a gas is ptm7/8 sseqwwoibk+a2g(g 85 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 - 0o*imsx3k 5lde-quvat the same temperature, the ratio of their rms speeds is equal to the inverse ratio of the square roots of their ulxe*ks- v3 -iqd0m5omolecular masses.

  What is the rms speed of nitrogen molecules conta cu/+bi 7)u jjuul3o1cined in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of aq:1 pjj jvslu:9c 4mwc.3yg /gn oxygen molecule at 0 $^{\circ} $ C    m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules.    round trips per sec

  What is the average distance between nitrogen molecules at S6rtv8 8vboz3fTP?    $ \times10^{-9 }$m

  (a) Estimate the rms speed of an amino acid whose molecular mqvsqk8j u-qe-2;r 0ev,( hhv qass is 89 u in a live esv,q20j (hq;-kuqqhv8-v ring cell at 37 $^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P ln/tbo aq3 2h+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 uraniu 1f7qyjc8p)wt 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, in whatc4 k oui7k +q0v*d)zondq1x ;a 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 phasei mahapdqfb oo ;dk 46*y)82*d when the pressure is 0.01 atm and the temperature is (a) 908fm*ok odadi ay)4h6 *2;b dqp $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximately) if the humidity is 50% on a day whenstil(3eb g)2j v* blm2 the tempsl3ilj 2t(m* vbb2e)gerature is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils kk)ps2n. kj9fat 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place in the mountains is 0.72 atm, *t5j r/if uh+bwe: ub3estimate the temperature at which water j*5uwi:reb b3 +fth/uboils. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when th /z0wjaex 7ggk)71fo ef0x bk)e partial pressure of water is 530 Pa and the relative humidity is 407og7)/ 0fakfwez) g exj k1bx0%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a d8 z*9td* ,tww;nwy lyway when the temperature is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure cooker if the wate m3 tc.vu**u/e1rift co;lt6sr is boiling at a temperature ofc le6ucruf *tsv.i/o;t13 t *m 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 volume 6; 8mra; iuhzhch*uf5680$m^3$ at 25 $^{\circ} $ C is 80%, what mass of water can still evaporate from an open pan?    kg

  Air that is at its de/o;e fg(lp7iyet-m , cw point of 5 $^{\circ} $ C is drawn into a building where it is heated to 25. What will be the relative humidity at this temperature? Assume constant pressure of 1.0 atm. Take into account the expansion of the air.    %

  Estimate the time needed for a glycine molecule (see Table v5lih6:qo 5k w13–4) to diffuse a distance of 1o k:h5 6liwvq55 $\mu m$ 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 t 9m92x gw6mj(l frxbh2s mp8 *ex*i.kghrough tiny tubes called tracheae. An average trachea is about 2 mm long and hasm* pm2kmx2lgbr je699fwxh g(8.xi*s 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 measuv dcf8+ d9 lzjm+gyu82re 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 measursmhfp72( gch8oatg zx:sg+ 5lzg0p5n+e6d7we has been calibrated at 20$^{\circ} $C. At 34$^{\circ} $C,
(a) will it read high or low,
(b) what will be the percentage error?    $ \times10^{-4 }$ %

  A Pyrex measuring cup was calibrated at normal room temperature. How1j cf:u4p63q fsuqfbkrg78 7 p much error will be mader7p74f: 6kuj38fq sqc1b fpgu in a recipe calling for 300 mL of cool water, if the water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a heli rx) .hph12qmkql u1)p9b/sycum gas cylinder is initially 28 atm. After many balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the original gas remains in the cys)p1 9u l.pbhm12k)rq q xhc/ylinder?   

  Estimate the number of air molecules in a room of length 6.5 m, width 5w90l*lzz2beh um 0sc 3.1 m, and height 2.5 m. Assume the temperaturesu0e 9 0mw5lz* 2bzlch is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is about onezd3kqgkn l- mj4 n9s 7mxx/b51 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 avc((yhccuj1 t5cqd0/v 2l f;d *d(kkfvailable vacuum techniques is about v(kjql(* tucdd5 ckd2y(c fh/v 01c;f $10^{-12} N/m^2$ 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 c(0v1dwhqab,m mq6:b+w ) ig- q/tsjfmapacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly ros mh 6mjab( iwd0s-qtvg1/+f,qq: m)wbe to the surface? Is this advisable?    L

  A space vehicle returning from the Moon enters Earth’s atmosphere at aayw)- bor r) **tqvxz8:lt 3czr4/t dr 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 bright btr*-ow tq:l)xr yrct)4r* z3zb v/ a8dlaze upon reentry.)    K

  The temperature of an ideal g1 ( ul,h/b *tsjtca:oyas 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 mmzntz pw j3oxupwwb;5+ 5 y1owo;);:of 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 v+khrg5o:vcs ws z1 .v 8u4l;eEarth, estimate .+gzcvr8 lv4 1owh usv ;:se5kthe total number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitrogen molecules conto(*rl adpzz08 ained 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 hospi/5 *ebq0wt*8epexrbk tal has gauge pressure = 2000 psi (13,800 kPa) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is /8eep5rbekx**qb0w t constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowl of lu+d45nix7dtm p5 oh6s iquid 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 gasolibe/d/-: l)orm m )tfpe r3qn5jne at 0$^{\circ} $C is 0.68$ \times10^{3 }kg/m^3$ What is the density on a hot day, when the temperature is 38$^{\circ} $C?    kg/$m^3$
What is the percentage change?    %

  If a steel band were to fit snugly around the 2ony( :df,rjn 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 tightl ) a9ogt q 3wgv1ycyx31bm gq,u4px2o0y onto a glass jar at 20$^{\circ} $C. To help open the jar, it can be placed into a bath of hot water. After this treatment, the temperatures of the lid and the jar are both 60$^{\circ} $C. The inside diameter of the lid is 8.0 cm at 20$^{\circ} $C. Find the size of the gap (difference in radius) that develops by this procedure.    cm

  The first length standard, adopt u oxe,y6 l1)lmym5e3ped 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 charg9 amcbk 8fc-w7ed, has a pressure of 195 atm at 20$^{\circ} $C. The volume of the tank is 11.3 L.
(a) What would the volume of the air be at 1.00 atm and at the same temperature?    L
(b) Before entering the water, a person consumes 2.0 L of air in each breath, and breathes 12 times a minute. At this rate, how long would the tank last?    min
(c) At a depth of 20.0 m of sea water and temperature of 10$^{\circ} $C, how long would the same tank last assuming the breathing rate does not change?    min

  The escape speed from the r*7/ ywala4m gEarth 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 s;3kdivi-e4f7v ej;r9oy( ct puspended against gravity by tennis balls thrown vertically upward at it. How many 3jkoe(9fc7d4pir;e t;-v v yitennis 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-d1qmochcy e/ *)iameter (spherical) bubble of air from a depth of 14.0 m in a lake. Assume the temperature isocc h)1*eqm/ y constant at 298 K, and the air behaves as a perfect gas. How large is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the ai;1gn gbrw0n hplu2,u2r on the following two days: un,nr g 0;buglh12wp2
(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 1z+:dwovpx,dsdv 3s4p , f:j tdifference in the density of iron at STP, and when it is a solid deep in the Ea+o, :jvpw fd1xd ds,4sp:z3tvrth 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 to show that, for an ideal gas at consd1h39o4d ltz ztant pressure, the coefficient of volume expansion is equal tdz9h4do3 1zl 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 cella/hzb4 htz89kngft7*;cy, pbyjio . 1irs to prevent rot and mildew. If 8h49/t ;ft i, jopgk.b*b71izyyznhcthe 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