Which has more atoms: 1 kg of iron or 1 kg of alumiu,ed25cr9lgo l)ug94jw)zm3ai zj, mnum? See the periodic table or oil,2 d gljemzz9u) 4cu ,9 gwm5rj3a)Appendix B.

Name several properties of materials that could bey.p3abyu( w-pfl. 4k i exploited to make a thermometer(.ayib- pyupf34 klw. .

Which is larger, 1 C:yi4bwlpe 6;mr 8af6 f $^{\circ} $ or 1 F $^{\circ} $?

If system A is in thermal equilibrium with system B, 5h5 /lo7 yw3 e6 ua5 tie6fmmy6)cpkuzbut B is not in thermal equilibrium with system C, 5e65y /mmy3)ulut5p7ocfwhk iz6 ae6what can you say about the temperatures of A, B, and C?

A flat bimetallic strip consists of aluminum puu.t(qb3w 2 h )graf/riveted to a strip of iron. When heated, the strip will bend. Which metal will be on the outside of the curve? [Hint:2(rbu /. tafu3h)q pgw 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 676 ycsssdezh*js4 *wlinear 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 control7 ng) 7 qmsoc6/amkzf+ a furnace (or other heating or cooling system). The bimetallic strip consists of two strips of different metals bonded together. The electric switch is a glass vessel containing liquid mercury ths/conf6z+ gmm) 7 qka7at 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 fixmotrcm, 2*wiz/2 :i9mpea j l.qi;vz5ed at the ends often have a section in the shape of a U. Whyle /cza; qo.imvri wmpmj :2t5,2*9iz?

A flat, uniform cylinder of lead floats rki**ucb4;t+ 2i lonwin mercury at 0 $^{\circ} $ C. Will the lead float higher or lower when the temperature is raised? Explain.

When a cold mercury-in-glass thermometer is first placed in a)e my2hb,lkyaf h/rvlk(-l*9 h- t *rn hot tub of water, the mercury initially descends a bit and t-eyy f(lm b-/rl*)vhnla9*2hhk k,rthen rises. Explain.

A glass container may break if one part of it is heated or cooled more rap h7f3g( gn 0kc1es0s/vqb3pb7 stz c9widly than adjacent parts.sp 7hzsb t3(1 30v0kg/wgqnf 7ec9b cs Explain.

The principal virtue of Pyrex glass is that its coefficient of linear exp:e:y/s1ly by)vdo gis 2kz2, iansion is much smaller than that for,o1yy lv/gdsi b2i) k:ey2zs: ordinary glass (Table 13–1). Explain why this gives rise to the increased heat resistance of Pyrex.

Will a grandfather clock, accuratej 7h; pie9b.wi r+n0ug 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 cauw: 6qmp0r p7c4fc(p emse its bottom and top to bulge so badly the can will not stand up. wpf(pq7e0p:m c4rcm6What has happened?

When a gas is rapidly compresseh*8u sf4 jwd5oe7gzf:v m/du.d (say, by pushing down a piston), its temperature increases. When a gas expands against a piston, it cools. Explain these changes in temperature using the kinetic theory, in particular noting what happens to the momentum of molecules when they strike the moving pim8 euu:4 og dfh*.5jv/zfd7ws ston.

Will the buoyant force on an alums3laxs/.wz , 8pjtjq4inum sphere submerged in water increase or decrease if the temperature is increased fro8.s43z txpj/q jl, wsam 20 $^{\circ} $ C to 40 $^{\circ} $ C?

Explain in words how Charl fzd1p-7n/o 8npl,s+dmm( d fges’s law follows from kinetic theory and the relation between average kinetic energy and the absolute tempergm-71sn fdpp/d n(8, flz+domature.

Explain in words how Gay-L .6;c : 7q;gespkorne4+sm;ddqc-b zgussac’s law follows from kinetic theory.

As you go higher in the Earth’s atmosphere, the/qbv8g. ebx whrj (q65 ratio of $N_2$ molecules to $O_2$ molecules increases. Why?

Escape velocity for the Earth refers to the minimum sp2 se7v2:dhv zjeed an object must have to leave the Earth and never return. The escad vh7j2e:z2sv pe 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*wvp+:s8d i oyb 0b-ml can you infer about the molecular properties of one relative to tdi* pbm+ swb08:v-y olhe other?

Explain why a hot humid day is far more uncomfortable than a hot nv9 7iji9x--9c ,mq vfk))fg3ylvfs vdry day at the same temperatu)f99ckv7) n jy 9,fqsfi vvm-xl3-vi gre.

Is it possible to boil water at room tem t .l+dhx(( +4o(/qssmckzhb rperature (20 $^{\circ} $ C) without heating it? Explain.

Consider two days when the air temperature is the same but the hu6rotm1 ,) a,oylgb 5trmidity is different. Which is more lgt trb) y6mao ,,r5o1dense, the dry air or the humid air at the same T? Explain.

Explain why it is dangerous to open the radiator cap of an overheated automoj2c5y f4bdm l+eys)3n bile en)3 f52dsbe clyjy+4 mngine.

Why does exhaled air appear ast69lm dxh;o+2k w;b pr a little white cloud in the winter (Fig. 13–28)?

  How many atoms are there in a 3.4-gram copper p +bo h 1290wu awfqahclw/p9lm7 tl sc2,i3vr8enny?   $ \times10^{22}$ atoms of Cu

  How does the number of atoms in a 26.5-gram gold ring compare to the number in .l bbrq8wxcyn,6/ mb/a silver ring of the sa/q bxc8rybml,nwb 6 /.me mass?$N_{Au}$ =    $N_{Ag}$

  “Room temperature” is often taken to be 68°F. Wo c(lg11ha)oyhat is this on the Celsius scale?yh(glo1) a oc1   $^{\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 x6nbj9wd.pib y76 lx( temperatures recorded are 136 $^{\circ} $F in the Libyan desert and -129 $^{\circ} $F in Antarctica. What are these temperatures on the Celsius scale?high =    $^{\circ} $ C
low =    $^{\circ} $ C

  (a) 15 $^{\circ} $ below zero on the Celsius scale is what Fahrenheit temperature?    $^{\circ} $ F
(b) 15 $^{\circ} $ below zero on the Fahrenheit scale is what Celsius temperature?   $^{\circ} $ C

  In an alcohol-in-glass thermometer, the alcohol cwd*upkm bn2 h,9ek9r5olumn has length 11.82 cm at 0. bkw2r p,9h5 *kudem9n0 $^{\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 o;yj 9gdbku *o1f 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. 13–29) is built of wroughtpwyqwgo z. 82m1gqy 25 iron approximately 300 m tall. Es 8gwy 5pzq1o2gqm wy2.timate how much its height changes between 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, rivets that are larger than the rivet hole are oftencqr2 +i.su7cx used and the r7u +sqx cci.2rivet is cooled (usually in dry ice) before it is placed in the hole. A steel rivet 1.871 cm in diameter is to be placed in a hole 1.869 cm in diameter at 20 $^{\circ} $ C. To what temperature must the rivet be cooled if it is to fit in the hole?    $^{\circ} $ C

  The density of water at 4 a07 *k5wglzot $^{\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 inpmj:b kv8l0g4kszw86 volume if it is m064bw:8skg8vpj k lzheated from 30 $^{\circ} $ C to 200 $^{\circ} $ C?    $ \times10^{ -2}cm^3$

  An ordinary glass is filled to the b5yl9uaow3x* 2*khddb ul+ic; rim 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 555tjzsgp o+q9vk)b* rm++p qj9 .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 ma ft+xr7cbbk.x8de7wx (/r /f cde 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 essentiallykw kdpf6m)hy4 1b3h:v one dib31p yf dm6kh:wv)k4h rection only, show that the effective coefficient of linear expansion is approximately equal to the coefficient of volume expansion $\beta$.

(a) Show that the change inay,g57-9cuvezqc xyh ( q (5* lggad8n 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 coefrbq(7*uh1od ey .:kd b-uz m7d3ljk-w ficient of linear expdr-7mbd3bj- ldy:q.w( 1eu* okhz7ukansion $\alpha$ 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 isotr y+9qrtp16. 2hczutlmopic solid, $\beta$ = 3$\alpha$ if the amount of expansion is small. $\beta$ and $\alpha$ are the coefficients of volume and linear expansion, respectively. [Hint: Consider a cubical solid, and neglect very small quantities. See also Problem 18 and Fig. 13–30.]

  The pendulum in a grandfathepsd8e y2p ;v6:e. b35v wmvqxxr clock is made of brass and keeps perfect time at 17 pqb5.v2d yxxwe8p;:e 3vm v6s$^{\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 0.11 * /r,2howvpvbf sdv340 mm. The bulb has a volume of 0r o,w /p132bdvvvf* hs.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 cylg muewbqja(;f 7 1hq47indrical wheel of radius 0.41 m is rotating about its1h7wqguq f;b7m(aej 4 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 th xuf2q-.h.v 7ba u oa1j ;:lq/njqv1bke desired length when at 15°C. How much stress is required to keep it at this length if the temperature inc2vn;lfq7ubxqvbku.j/1aj 1 oh a. :-q reases to 35 $^{\circ} $ C?    $ \times10^{7 }$ N/$m^2$

(a) A horizontal steel I-beam of crosspi0,lu(aa5 mhxdbjof y) ;51s-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 134.12yp6j f* 2n.(f n85da b vq-i(cjgsxlw-2 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 followinmdg8z:: nn73s6t .wk0au vhwzg temperatures on the Kelvin scale:
(a) 86$^{\circ} $ C,    K
(b) 78$^{\circ} $F,    K
(c) -100$^{\circ} $C    K
(d) 5500°C,    K
(e) -459$^{\circ} $F    K

  Absolute zero is what temperature on thep8s )/qps cn/r Fahrenheit scale?    $^{\circ} $ F

  Typical temperatures in the intjmtd k8(z9imgxh vs-:)/v4 igerior 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 engine, air at att,rb e a2n *bkqg/y1s8mospheric pressure and a temperature of about 20nbg8sr2 ae q*/kt,y 1b$^{\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 oxyg- cox-m; p5pqmen at STP using the ideal gas law.    kg/$m^3$

  A storage tank contains 21.6 kg of nitrogen kebn -ve4rukc;j/ 4o2z+ ,wzc($N_2$) 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 d/p v4o (qdze*nitrogen ($N_2$)
(a) What is the volume of the tank? $\approx$   $m^3$(“Round to one decimal places)
(b) What is the pressure if an additional 15.0 kg of nitrogen is added without changing the temperature?    $ \times10^{5 }$Pa    atm

  If 18.75 mol of helium gas is at 1wbml )wm +prp0*fbd/;0.0$^{\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 35.3rxqhn* f-iq+ 0-L container holding 105.0 kg of argon gas at 3 +qqi*x3nfrh -85 K?   $ \times10^{ 8}$Pa

  A tank contains 26.0 kgnmz6xi:xnvf() 2o e+s 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 ballo0u;,btt w z0sqon, which makes it less dense than the air outside. Supposq;ttbz00,w u se 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 1 93un x+wuzpc+oipt/+ 5 $^{\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 x *l*rgt:e6*f,iy c2hu a,ezt18.0 $^{\circ} $ C and an absolute pressure of 2.45 atm are compressed to 48.8 L and at the same time the temperature is raised to 50.0°C, what will the new pressure be?    atm

  A helium-filled balloon escapes a child’s hand at20 qb y64njhvqswr:raeuw*9 9 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 mocmxa rr0fke c*b7yfg6f 9,nk.4 c t:zj*v2;p ylecules / $m^3$ in an ideal gas at STP.    $ \times10^{25 }$ molecules /$m^3$

  How many moles of water are there in 1.000 L? How man5u6) naaxif:m y molecules?    mol    $ \times10^{25 }$ molecules

  Estimate the number or;bgx- hv70/ 3tnxqds 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 volume 5.* 63+.l2qawroitaf mgc:gb p )cruo60 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 airr0ee lejanu )ax ,)1.y are in each 2.0-L breath you inhale that were also in th a)a)exy . uej,r0ln1ee last breath Galileo took. [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 oxyor 7py he3kbw;g5v3x5gen molecule at STP? ;7 kv53 e5 rgpw3yxbho   $ \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 of4pk8gexpay 71 the Sun at a temperature of akgy8 7xpe 14apbout 6000 K.    m/s

  By what factor will thetoiv/ l e7y 3wfdcff*bi:n nl,1i/u:6 rms speed of gas molecules increase if the temperature is incree: 36 7o 1l ntfd/b/:iy,f*cunfviilw ased 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 speed yp.ku1iv :v1 yupowp.4dx- 0ds, given in units of km/s: 6, 2, 4, 6, 0, 4, 1, 8, 5, 3, 7, and 8. Calculate4v v1 pxu.io0wu-p1pk yydd:. the rms speed. $v_{rms}$ =    km/s

  The rms speed of molecules in a gas at 20t/tv3 ylv 2s)va8l exxg8,sv3 .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 double nb:c t8.itsi*d while its volume is held constant, by what factorcbstti: .n8i* does $v_{rms}$ change?   

Show that the rms speed of moleculdpe+r :lffo)e90 )hzo(urnl (es 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 garsro3vuxa us6 e u6ac96xp/4ou( l/ c+ses at the same temperature, the ratio of their rms speeds is equal to the inver psuv/6 oa6ou lx9cu4/ex(csru+3ra6 se ratio of the square roots of their molecular masses.

  What is the rms speed of nitrogen molecules contao:5hlll 1r zt-ined in an 8.5$-m^3$ volume at 2.1 atm if the total amount of nitrogen is 1300 mol?    m/s

  Calculate (a) the rms speed of an oxygen molf p* sczn007 pp:szoqm2)dl6y ecule 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 STP8ofv aq)yjjd;3 *:p(k0l mmo1+lpctb?    $ \times10^{-9 }$m

  (a) Estimate the rms 8x8 jcs zj* *lbi0e0zaspeed of an amino acid whose molecular mass is 89 u in a living cell at 37 x 8jas0l0ecb*8iz jz*$^{\circ} $ C.    m/s
(b) What would be the rms speed of a protein of molecular mass 50,000 u at 37 $^{\circ} $ C?    m/s

Show that the pressure P of a gas can be-y twf1 4p z.4qq0gdpkyw 8bb vt-z2*p 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 ur. .f/ouj k 0xwhlnv 0vok/;6ivanium, $^{235}$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 what phases k: hh(j:k -vsn */s tsljf3 030exkryhcan $CO_2$ 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 tha,sx9h/jz r4 jqh*kw *e pressure is 0.01 atm and the temperature is (a) 90jk wzha*,49rxsq h* /j $^{\circ} $ C, (b) -20 $^{\circ} $ C.

  What is the dew point (approximat z.rqko;i, upp7fix0r x1(9ia ni4o l*ely) if the humidity is 50% on a day when the temperaturix0lzriu.o7n1a p kp4i qfoi (*9x,; re is 25 $^{\circ} $ C?$\approx$    $^{\circ} $ C(Round to the nearest integer)

  What is the air pressure at a place where water boils 6q v4pn4h8qoyat 90 $^{\circ} $ C?    torr    Pa    atm

  If the air pressure at a particular place 3fqucu*xw4 a.in the mountains is 0.72 atm, estimate the temperature at which water boilsc u4*wu3 qx.fa. $\approx$ =    $^{\circ} $ C

  What is the temperature on a day when t1sxb;afv:/uc( d xvtqu j hz3 p:+zhxz5 u,;8khe partial pressure of water is 530 Pa and the rela,vxjcs:hpvd qb; 831u/t5uu (kfzh+ a:x zz;xtive humidity is 40%? $\approx$ =    $^{\circ} $ C(Round to the nearest integer)

  What is the partial pressure of water on a day when the temperature yd *aani;wi1, is 25 $^{\circ} $ C and the relative humidity is 35%?    Pa

  What is the approximate pressure inside a pressure jrijyl y3s, )al9pyll 7(*l+ cap)0ko;yrwz1cooker if the water is boiling at a temperature31w9y)s(*ylprl7c,p 0j)+i z oarll l yyj;a k 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 vo;9yl 0wb6*o j j;vm cldkbr4d5lume 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 p; t1 zum1ff;jam- :y6lgi qjloxd57 p(oint 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 wi-7xdv+i*hne ,q 09o5w usxxglycine molecule (see Table 13–4) to diffuse a diswo-*q5 e,v9 7 0h nusx+ixwdxitance 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 sq.l 6wy lwb7hx- e*a:*+jnd ztubes called tracheae. An averahj76ll*ew.bysn z- *d+ xawq :ge trachea is about 2 mm long and has cross-sectional area of $ 2\times10^{-9 } m^2$ Assuming the concentration of oxygen inside is half what it is outside in the atmosphere,
(a) show that the concentration of oxygen in the air (assume 21% is oxygen) at 20$^{\circ} $ C is about 8.7 mol/$m^3$ then $\approx$    mol/$m^3$(Round to one decimal places)
(b) calculate the diffusion rate J,    $ \times10^{-11 }$ mol/s
(c) estimate the average time for a molecule to diffuse in. Assume the diffusion constant is $ 1\times10^{-5 } m^2/s$    s

  A precise steel tape measure has been calbk c u-aup-2:hibrated 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 calibrzowh 71ux ny):;.yxot ated 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 much error a 2gubigspi0e 2w6 :wzy4-;nht( : gvcy(w6bpwill be made in a recipe calling for 300 mL of cool water, if the p0i wy(vbpszu;6(i cg: gen y:w-2 ahwtb26g4 water and the cup are hot, at 80$^{\circ} $C, instead of at 20$^{\circ} $C? Neglect the glass expansion.$\approx$    ml

  The gauge pressure in a helium gas cylinder is initially 28 atm. After m6p qda t) rv3rut-op /5c,l*dhany balloons have been blown up, the gauge pressure has decreased to 5 atm. What fraction of the origin at-/*,vh5dlu)d pto3qrc 6rp al gas remains in the cylinder?   

  Estimate the number of 6-qkkg i, n0d/kp+g ua+e8iwxair molecules in a room of length 6.5 m, width 3.1 m, and height 2.5 m. Assume the temperature-q gdki,kgaux new8k6 / ip0++ is 22$^{\circ} $C. How many moles does that correspond to?    $\times10^{27 }$ molecules    moles

  In outer space the density of matter is abae j8phish4dj iz+zjd):- )( j;, pdpaout one atom per $cm^3$ mainly hydrogen atoms, and the temperature is about 2.7 K. Calculate the rms speed of these hydrogen atoms, and the pressure (in atmospheres).$v_{rms}$ =    m/s    $ \times10^{-22 }$ atm

  The lowest pressure attainable using the .k rxi)v(cf z):+v oic;fau(bbest available vacuum techniques is abou(fcoa;)kr)ix+u:v c ifb(v.z t $10^{-12} N/m^2$ 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 lungwgka4a 5vs7i i1eqj 9h lreygm-1(2,cs to full capacity of 5.5 L when 10 m below the surface, to what volume would his lungs expand if he quickly rose to the surface? Is this advisable va7iwe4cysrm 1 gh- 9eqjkgi5a21 (l,?    L

  A space vehicle returning from the Moon enters Earth’s atmos,lq273as kq h5dqmpx -phere 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? (Bed qals7p5kq-xh3 2q,m cause 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 ins7v1 pme ol8 ;)ewp6ckcreased 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 ofvp ;k2ru:oc z c+ yefi5bu2/bt,1-nrw 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 press:bfbtsk*- +tgecwq6 b4c6c6 gure at the surface of the Earth, estimate tb 6cctqf-se:bkwgt+4b6*6g c he total number of air molecules in the Earth’s atmosphere.    $ \times10^{44 }$ molecules

  What is the rms speed of nitr-cm yq ,;l(dx2hoa aa(ogen molecules contained in a 7.6$-m^3$ volume at 4.2 atm if the total amount of nitrogen is 1800 mol?    m/s

  A standard cylinder of oxygen used in a hospital has gauge pressure l2czs: )eg n)uq.*dvz= 2000 psi (13,800 kP:2*zz ))qcngev ls .uda) and at T = 259K How long will the cylinder last if the flow rate, measured at atmospheric pressure, is constant at 2.4 L/min. $\approx$    hour

  An iron cube floats in a bowlj;pt p1n5 uk5i of liquid mercury at 0$^{\circ} $C. (a) If the temperature is raised to 25$^{\circ} $C, will the cube float higher or lower in the mercury? ----待选择----lowerheigher 
(b) By what percent will the fraction of volume submerged change?    %

  The density of gasoli9 )nzkl es(x 94b8jdxsne 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 Earth’s e2kg/hv .ynvc.4 l -tme0hl/soquator at 25$^{\circ} $C, but then was heated to 45$^{\circ} $C, how high above the Earth would the band be (assume equal everywhere)?    m

  A brass lid screws tightly onto a glass1l4 bl-*b6gdne,2i9, kgvdw1wld hcn 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, adop8cjv)(wpn * k-avrt.lb e/- ojted 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 19xtb jk9ooo7 ym2 f4k7-fgt39d5 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 froc-ye z 3nmneb,xg+gt4 i9 -1qcm 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;,jme ho 9dv3k by tennis balls thrown vertically upward at it. How many tennis balls per second must rebound from the lid elastically, assuming they have a mass ok ,j;d9om h3vef 0.060 kg and are thrown at 12m/s   balls/s

  A scuba diver releases a 3.00-cm-diameter (spherical) bubble of air from a depthw k;+vinjiy4cqlr-(gqn hi o* e542w+ of 14.0 m in a lake. Assume the temperature is constant at 298 K, and the air behaves as a perfect gas. How lae(; w2 4*5jy4qvnic+ro+ klqg - iwnihrge is the bubble when it reaches the surface?    cm

  Calculate the total water vapor pressure in the air on the folllrtn2oh 920 rvowing two days: ht29n0o2vlrr
(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 uz x va3(cbu x*1ozpk3-tej57in the density of iron at STP, and when it is a solid deep in the Earth where the temperature is 20bx c z 353utj(7vxk-1 oeaz*up00$^{\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 constant pressure, l 7n/ae.j+bf1 2 6:uzatu bwircbp x;)the coefficient of v;7e1jbtz6u/l bprw: .nc )xauibaf 2 +olume 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 c+ c)fkrgmpf(h 7ji 0qs.(zv 3uonstantly dehumidify their cellars to prevent rot and mildew. If the celjmr pk q0vcfg7.i3 h(u+(s zf)lar 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