A.V.

How many liters in a standard bath 170 cm and 150 cm?

Modern accommodation allows you to ensure complete comfort for living, this also applies to heat and the possibility of using water. Bathing in the bath is so firmly in use, which does not think already that in the near past the past was forced to walk in the bath. An increase in the cost of utilities makes thinking how expensive is to pay for water, which is used when bathing in a standard bath.

Baths: species, models

Choosing a bath, you should pay attention to many aspects: the material from which it is made, shape, the size, the thickness of the walls. Important value has a protective coating of a bath, which will allow to exploit equipment for many years.

Baths are made from various materials:

Bath sizes

Baths are available with dimensions:

• Symmetric models - from 120 × 120 cm to 180 × 180 cm.
• Asymmetric models - from 120 × 60 cm to 190 × 170 cm.

Traditional baths have dimensions:

• Sitting - from 120 × 70/75/80 cm.
• Full-size - from 150 to 180 × 70/75/80 cm.

How many liters of water enters the bath

By purchasing a bath, it is worth paying attention to the technical characteristics of the plumbing equipment, having studied the passport details. Typically, the passport shows the main dimensions and volume that is maximally allowed to pour the specified model to the bath.

If the volume of the product is not specified by the manufacturer, you can calculate it yourself. To do this, it is necessary to make some measurements: the length, width and depth of the bowl. 1 dm3 (1000 cm3, 0.001 m3) contains 1 liter of water.

The calculation is made according to the formula: V (volume) \u003d H x L x S.

• H - depth.
• L - Length.
• S - width.

A standard value bath with a size of 170 x 70 x 50 cm accommodates about 595 liters of water. The bath with dimensions of 150 x 65 x 50 accommodates about 487.5 liters of water.

How to choose a bath: video

8.1. When operating an electric motor with a capacity of 400 W, it heats up 10 to 50 from continuous operation. What is the efficiency (in percent) of the motor? Motor heat capacity 500 j / k.

8.2. The generator radiates ultra-high frequency pulses with energy in each pulse of 6 J. The frequency of repetition of the pulses of 700 Hz. CPD generator 60%. How many liters of water per hour should be passed through the cooling system of the generator so that water is not higher than 10 k? Specific heat capacity of 4200 J / (kg-k).

8.3. For heating some mass of water from 0 ° C to 100 ° C, 8400 J warmth is required. How many heat still need (in KJ) to completely evaporate this water? Specific heat capacity of 4200 j / (kg-k), specific heat of water vaporization 2300 kJ / kg

8.4. To cool the water in the refrigerator from 33 ° C to 0 ° C, it was required 21 minutes. How long will it take to turn this water into ice? The specific heat capacity of 4200J / (KG-K) water, the specific heat of melting ice is 3.3105 J / kg. Answer to give in minutes

8.5. Calculate the efficiency (as a percentage) of the gas burner if it uses gas with heat combustion 36 MJ / M3, and 60 L of gas was spent to boil from 3 liters of water from 10 ° C to boil. The heat capacity of the kettle is 600 j / k. Specific heat capacity 4200J / (kg-k).

8.6. What is the height of the waterfall, if the water temperature at its base is 0.05 ° C, more than at the top? It is considered that all mechanical energy goes to water heating. The specific heat capacity of water is 4200 J / (kg-k), G \u003d 10m / s 2.

8.7. Which height could be raised the load weighing 100 kg, if it was possible to completely turn the energy secreted during cooling of a glass of water from 100 ° C to 20 ° C? The mass of water in a glass of 250 g, the specific heat capacity of water is 4200 j / (kg-k), the heat capacity of the glass is not taken into account, G \u003d 10m / s 2.

8.8. The body slides with an inclined plane with a length of 260 m and an angle of inclination of 60 °. The coefficient of friction about the plane 0.2. Determine how much degrees will increase the temperature of the body if 50% of the heat distinguished heat is in its heating. The specific heat capacity of the material from which the body is made is 130 J / (kg-k). G \u003d 10m / s 2.

8.9. Two identical balls made from a substance with a specific heat capacity of 450 J / (kg-k), moving towards each other with a 40m / s and 20m / s speeds. Determine how much degrees they heat as a result of an inelastic collision

8.10. From what height (in km) should the tin ball should fall so that when you hit the surface, it completely melted? It is considered that 50% of the energy of the ball goes to its heating and melting. The initial temperature of the ball is 32 ° C. Melting point of tin 232 ° C, its specific heat capacity 200 J / (kg-k), the specific heat of melting 58 kJ / kg. G \u003d 9.8m / s 2.

8.11. To prepare a bath with a capacity of 200 liters, cold water was mixed at 10 ° C with hot at 60 ° C. How many liters of cold water should be taken to set the temperature of 40 ° C in the bath?

8.12. The thermometer showing the temperature of 22 ° C is lowered into the water, after which it shows the temperature of 70 ° C. What was the temperature (in ° C) of water to immerse the thermometer? Water weight 40 g, specific heat capacity of 4200 j / (kg-k), heat capacity of the thermometer 7 j / k.

8.13. In the calorimeter, three chemically non-interacting non-freezing fluids are mixed with masses of 1 kg, 10 kg and 5 kg with specific heat capacities 2, 4 and 2 kJ / (kg-k), respectively. Temperatures of the first and second liquids before mixing were 6 ° C and -40 ° C. The temperature of the mixture was equal to -19 ° C. Find the temperature (in ° C) of the third fluid before mixing.

8.14. The vessel containing 9 kg of water at 20 ° C is introduced by I kg of steam at 100 ° C, which turns into water. Determine the final temperature (in ° C) of water. The heat capacity of the vessel and the loss of warmth is not considered. The specific heat capacity of water is 4200 J / (kg-k), the specific heat of water vaporization of 2.3 MJ / kg.

8.15. Bath with a capacity of 85 l must be filled with water having. The temperature is 30 ° C using water at 80 ° C and ice at a temperature of -20 ° C. Identify the mass of ice to put in the bath. The specific heat of melting ice 336 kJ / kg, the specific heat capacity of ice 2100J / (kg-k), the specific heat capacity of the water is 4200 J / (kg-k).

8.16. The vessel has some amount of water and the same amount of ice in a state of thermal equilibrium. Through the vessel passes water steam at a temperature of 100 ° C. Find the steady water temperature in the vessel if the mass of the passed steam is equal to the initial mass of water. The specific heat capacity of water is 4200 J / (kg-k), the specific heat of water vaporization of 2.3 mJ / kg, the specific heat of melting ice 330 kJ / kg.

8.17. In a cylinder with a base area of \u200b\u200b100 cm 2, there is a gas at a temperature of 300 K. at a height of 30 cm on the base of the cylinder is a piston weighing 60 kg. What kind of work is gas when expanding, if its temperature is slowly increased by 50 ° C? Atmospheric pressure 100 kPa, g \u003d 10m / s 2.

8.18. One mole of gas is isohoreanly cooled so that its pressure decreased 5 times, and then it washed up to the initial temperature of 400 K. What kind of work made gas? Universal gas constant 8300 J / (Komol-K).

8.19. The perfect gas in the amount of 4 mole is expanding so that its pressure changes directly proportional to the volume. What is the operation of gas with an increase in its temperature on 10 k? Universal gas constant 8300J / (Kombol-K).

8.20. In the isothermal process, the gas made a job of 1000 j. How much will the internal energy of this gas increase, if it is reported to the amount of heat, twice as large as in the first process, and the process is projected?

8.21. To heat some of the ideal gas with a molar mass of 28 kg / kmol on 14 K with constant pressure, 29 J warm blood took. In order to then cool the same gas to the starting temperature at a constant volume, it needs to take 20.7 J heat. Find a mass (in d) of gas. Universal, gas constant 8300J / (kmol-k).

8.22. A certain amount of ideal single-nuclear gas during isobar heating receives 10 J heat. What kind of work will this gas do with adiabatic cooling before the initial temperature?

8.23. The perfect single-nuclear gas in the amount of 1 mole was heated first isoogorno, and then isobaro. As a result, both the pressure and the volume of gas increased twice. What amount of heat got gas in these two processes, if its initial temperature was 100 k? Universal gas constant 8300J / (Kombol-K).

8.24. The two thermally insulated vessels of the same volume are connected by a thin tube with a crane. In one vessel, it is helium at a temperature of 200 K, and in the other - helium at a temperature of 400 K and at a pressure of 3 times greater than in the first vessel. What will get the temperature of the gas after opening the crane and the establishment of thermal equilibrium?

8.25. In the vertical heat-insulated cylinder under the piston there is a certain amount of helium at a temperature of 240 K. On the piston lies the weight of the mass equal to half the piston mass. The cargo instantly removes and wait for the system coming to equilibrium. What will be the temperature (in Kelvin) gas equal? No gas piston.

8.26. The working fluid of the ideal heat machine operating on the carno cycle is obtained from the heater with a temperature of 273 ° C with the amount of heat 80 kJ. The role of the refrigerator plays surrounding air, the temperature of which is 0 ° C. What maximum height this car can raise the load weighing 400 kg? G \u003d 10m / s 2.

8.27. Two moles of gas are isolated from 400 to 800 K, then the iso-horror is cooled to 500 K. Next, the gas is cooled in it so that its volume is reduced to the initial one. Finally, gas isochloride heat up to 400 K. Find the work perfect with gas in this cycle. Universal gas constant 8300 J / (Komol-K).

8.28. The ideal single-name gas performs a cyclic process consisting of isoormal cooling, in which the gas pressure decreases four times, then the isobaric compression and, finally, return to the initial state in the process in which the pressure changes directly proportionally. Find the efficiency of the CPT (as a percentage) cycle.

8.29. The ideal refrigerator operating on the back cycle of carno uses as a refrigerator with melting ice at a temperature of 0 ° C, and as a heater - boiling water at 100 ° С how the mass (in d) ice is formed upon receipt of 25 kJ from the energy network? Specific heat melting ice 3.25 * 10 5 J / kg.

8.30. What mass (in d) water should be additionally evaporated in a room of 49.8 m3 so that at a temperature of 27 ° C increase relative humidity from 25% to 50%? The pressure of saturated vapor water at a temperature of 27 ° C is 3.6 kPa, the molar mass of water is 18 kg / kmol, the universal gas constant is 8300 J / (Kolk).

8.31. In a closed greenhouse with a volume of 33.2 m 3, the relative humidity during the daytime at a temperature of 27 ° C was 75%. What a mass (in d) of dew will fall in the greenhouse at night, when the temperature drops to 15 ° C? The pressure of saturated, vapor water at a temperature of 27 ° C is 3.6 kPa, at a temperature of 15 ° C- 1,7kpa. The molar mass of water is 18 kg / kmol, the universal gas constant is 8300 J / (Komol-K).

8.32. In a vessel, at a temperature of 100 ° C, there is a moist air with a relative humidity of 40% under pressure I atm. The volume of the vessel is isothermally reduced 5 times. What will be the end pressure (in atm)? The volume of condensed water neglected

8.33. In the vessel, the volume of 10 liters is wet air with a relative humidity of 40% under pressure of 1 atm. How much percent increases pressure, if in addition to the vessel, to introduce 4 g of water? The temperature in the vessel is maintained equal to 100 ° C. Universal gas constant 8.31 J / (molk).

8.34. Determine the inner radius (in mm) of the capillary tube, if the water in it rose to a height of 14.4 mm. Water completely wets the glass of the capillary tube. The coefficient of surface tension of water 72 mn / m. G \u003d 10m / s 2.

8.35. In the same capillary tubes, water rose by 144 mm, and alcohol by 55 mm. Considering wetting complete, find alcohol density according to these data. The surface tension coefficient of water "72 mn / m, alcohol 22 mn / m.

8.36. On some planet, the water rose on a capillary tube for 8 mm, and on Earth along the same tube by 12 mm. What is the acceleration of free fall on this planet? G \u003d 10m / s 2.

8.37. In the capillary tube, lowered into a mercury vessel, a level 15 mm lower than in a vessel. Water poured into the vessel over mercury, as a result of which mercury levels are compared. Find the height (in mm) of the water layer. Mercury density of 13.6 times more water density.

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From here T.2 = 2T.1 \u003d 600 K.

As the gas transition is 2-3 isothermal, then T.2 = T.3.

Thermal CPD of the cycle is determined by the expressionHttps: //pandia.ru/text/80/300/images/image149_4.gif "width \u003d" 114 "height \u003d" 50 src \u003d "\u003e, (1)

Q.1 - the amount of heat obtained from the heater per cycle,

Q.2 - the amount of heat, given to the refrigerator per cycle.

Gas gets the amount of heat in sites 1-2 and 2-3

Q. 1= Q. 1-2 + Q. 2-3,

https://pandia.ru/text/80/300/images/image151_4.gif "width \u003d" 204 "height \u003d" 32 src \u003d "\u003e - the amount of heat obtained during isothermal expansion.

Gas gives the amount of heat in a plot 3-1 with isobaric compression:

Q. 3-1 = Q. 2 = cf. https://pandia.ru/text/80/300/images/image147_4.gif "width \u003d" 13 height \u003d 25 "height \u003d" 25 "\u003e

- molar heat capacity of gas at V. \u003d const

cf. \u003d https: //pandia.ru/text/80/300/images/image147_4.gif "width \u003d" 13 "height \u003d" 25 "\u003e

Substituting meanings Q. 1 I. Q. 2, fromv I. with R.in formula (1), we get:

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Answer: T. 2 = T. 3 \u003d 600 k, η \u003d 9.9%.

Task 8. .

It is necessary to melt 0.2 kg of ice having a temperature of 0 ° C. Is this task if the power consumption of the heating element is 400 W, thermal losses are 30%, and the heater hours should not exceed 5 minutes?

The amount of heat spent on melting ice is equal

https://pandia.ru/text/80/300/images/image160_3.gif "width \u003d" 77 "height \u003d" 32 "\u003e, then the task is fulfilled.

Answer: The task is done.

Task 9. .

The bath capacity of 85 l must be filled with water having a temperature t.\u003d 30 ° C using water at temperatures tB\u003d 80 ° C and ice when tl\u003d -20 ° C. Identify the mass of ice to put in the bath. The specific heat of melting ice 336 kJ / kg, the specific heat capacity of ice 2.1 kJ / (kg · k), the specific heat capacity of water is 4.2 kJ / (kg · k).

Full bath water will be provided

, (2)

where ρ - density of water, V.- Bath volume.

Solving the system of equations (1) and (2), we get:

https://pandia.ru/text/80/300/images/image164_0.jpg "Align \u003d" Left "width \u003d" 169 height \u003d 167 "height \u003d" 167 "\u003e Task 4.

One mole of perfect one-nose
gas first expanded isothermally
(T1 \u003d 300 K). Then gas was cooled, lowered the pressure 3 times (see Figure). What amount of warmth gave gas to a plot 2 - 3?

Answer: 2493 J.

Task 5.

10 moles of one-nominal ideal gas were first cooled, reducing the pressure 3 times, and then heated to the initial temperature of 300 K (see figure). What amount of heat got gas at a plot 2 - 3?

Answer: 41.6 kJ.

Task 6.

One mole of perfect single-nuclear gas was first cooled, and then heated to the initial temperature of 300K, increasing the volume of gas 3 times (see figure). What amount of heat gave gas in a plot of 1-2?

Answer: 2.5 kJ.

Task 7.

One mole of one-nominal ideal gas passes from state 1 to state 3 in accordance with the plot of its volume V.from temperature T.(T.0 \u003d 100 K). In a section 2 - 3, 2.5 kJ of warmth are applied to the gas. Find the cost of gas BUT123 To all the amount of heat supplied to the gas Q.123.

Answer: 0,5.

Task 8.

With one mile of perfect single-nuclear gas process 1-2-3-4, shown in the figure in the coordinates r-T..

How many times is the amount of heat obtained by gas in process 1-2-3-4 more gas operation in this process?

Answer:.

Task 9.

One mole of argon, located in the cylinder at temperatures T.1 \u003d 600ºК and pressure r1 \u003d 4 · 105 Pa, expands and at the same time cools so that its temperature when expansion is inversely proportional to the volume. Finite pressure Gaza r2 \u003d 105 Pa. What work gas made when expanding, if he gave the refrigerator the amount of heat \u003d 1247 J?

Answer: BUT ≈ 2493 J.

Task 10.

In the cylinder, closed by moving piston, is the perfect gas. It is translated from state 1 to state 2, and then to state 3, as shown in the figure (- change in the internal energy of the gas, Q. - the amount of warmth transmitted to him). Is the volume of gas change in the process of experiment, and if it changes, how? Answer justify, indicating which physical patterns you used to explain.

Task 11.

A horizontal cylinder with a piston is fixed in vacuo. The cylinder is 0.1 mol helium. The piston is retained by the stops and can slide to the left along the walls of the cylinder without friction. The piston falls a bullet with a mass of 10 g, flying horizontally at a speed of 400 m / s, and stuck in it. Helium temperature at the time of stopping the piston in the extreme left position increases by 64ºК. What is the mass of the piston? Assume that during the movement of the piston gas does not have time to exchange heat with the piston and cylinder.

a) heating and cooling

853. 2 kg of water was mixed in the calorimeter at a temperature of 50 ° C and 3 kg of water at a temperature of 30 ° C. Find the temperature (in ° C) of the mixture. The heat capacity of the calorimeter is not taken into account.

854. 210 kg of water poured in the bath at 10 ° C. How many water at 100 ° C should be added to the bath to heat the thermal equilibrium at 37 ° C?

855. It is necessary to mix water at a temperature of 50 ° C and water at a temperature of 10 ° C so that the temperature of the mixture is equal to 20 ° C. How many times do you need to take cold water than hot?

856. To prepare a bath with a capacity of 200 liters, cold water was mixed at 10 ° C with hot at 60 ° C. How many liters of cold water should be taken to set the temperature of 40 ° C in the bath?

857. The hot body at 50 ° C is shown in contact with a cold body at 10 ° C. When the thermal equilibrium is reached, the temperature of 20 ° C was established. How many times the heat capacity of the cold body is greater than the heat capacity of the hot?

858. The copper body, heated to 100 ° C, is omitted into the water, the mass of which is equal to the mass of the copper body. The thermal equilibrium has come at a temperature of 30 ° C. Determine the initial temperature (in ° C) of water. Specific heat capacity of 4200 J / (kg × K), copper 360 J / (kg × K).

859. Determine the initial temperature (in Kelvin) Tin weighing 0.6 kg, if it is immersed in water weigh 3 kg at a temperature of 300 to water heated on 2 K. Specific heat capacity of 250 J / (kg × K), water 4200 J / ( kg × k).

860. In the vessel poured 0.1 kg of water at a temperature of 60 ° C, after which the water temperature dropped to 55 ° C. Considering that the heat capacity of the vessel is 70 J / K, and the specific heat capacity of the water is 4200 J / (kg × K), find the initial temperature (in ° C) of the vessel.

861. To measure the temperature of the water weighing 20 g, the thermometer was loaded into it, which showed 32.4 ° C. What is the actual temperature (in ° C) of water, if the heat capacity of the thermometer is 2.1 j / k and before immersion in the water, it showed the temperature of the room 8.4 ° C? Specific heat capacity of 4200 J / (kg × K).

862. The thermometer showing the temperature of 22 ° C is lowered into the water, after which it shows the temperature of 70 ° C. What was the temperature (in ° C) of water to immerse the thermometer? The mass of water is 40 g, the specific heat capacity of 4200 J / (kg · k), the heat capacity of the thermometer 7 j / k.

863. After lowering into water, having a temperature of 10 ° C, the body heated to 100 ° C was set to a temperature of 40 ° C. What will be the temperature (in ° C) of water, if, without removing the first body, to lower the same body into it, heated also to 100 ° C?

864. The body heated to 110 ° C was lowered into a water vessel, as a result of which the water temperature rose from 20 ° C to 30 ° C. What would have become the temperature (in ° C) of water, if one of the same body was lowered at the same time, but heated to 120 ° C?

865. In the calorimeter, three chemically non-interacting non-freezing fluids are mixed with masses 1, 10 and 5 kg with specific heat caps 2, 4 and 2 kJ / (kg · k), respectively. Temperatures of the first and second liquids before mixing were 6 ° C and -40 ° C. The temperature of the mixture was equal to -19 ° C. Find the temperature (in ° C) of the third fluid before mixing.

b) phase transformations

866. In a vessel containing 9 kg of water at 20 ° C, 1 kg of steam is introduced at 100 ° C, which turns into water. Determine the final temperature (in C) of water. The heat capacity of the vessel and the loss of warmth is not considered. Specific heat capacity of 4200 j / (kg · k), specific heat for water vaporization 2.1 · 10 6 J / kg.

867. Some mass of water with the initial temperature of 50 ° C is heated to the boiling point, passing steam through it at a temperature of 100 ° C. How many percent will increase the mass of water? Specific heat capacity of 4200 J / (kg × K), the specific heat of water vaporization 2.1 × 106 J / kg.

868. In two vessels there are 4.18 kg of water at the same temperatures. 0.42 kg of water is poured into the first vessel at a temperature of 100 ° C, the second is introduced as much as water vapor at a temperature of 100 ° C. How much degrees the temperature in one vessel will be greater than in the other, after establishing thermal equilibrium in each of them? The specific heat capacity of water is 4200 J / (kg × K), the specific heat of water vaporization of 2.3 MJ / kg.

869. The vessel containing 4.6 kg of water at 20 ° C is thrown a piece of steel 10 kg, heated to 500 ° C. Water heats up to 100 ° C, and part of it appeals to par. Find a mass (in d) formed steam. The specific heat capacity of water is 4200 J / (kg × K), the specific heat of the water vaporization of 2.3 × 106 J / kg, the specific heat capacity of the steel is 460 J / (kg × K).

870. In a liter of water at a temperature of 20 ° C, a volume of 250 g was broken, partially already melted, i.e. containing some water at 0 ° C. The temperature of the water in the vessel when the thermal equilibrium is reached, it was equal to 5 ° C. Determine the amount of water (in d) in a coma of snow. The specific heat of melting ice 330 kJ / kg, the specific heat capacity of 4200 J / (kg × K).

871. The bath with a capacity of 85 l must be filled with water having a temperature of 30 ° C using water at 80 ° C and ice at a temperature of -20 ° C. Identify the mass of ice to put in the bath. Specific ice melting 336 kJ / kg, specific ice heat capacity 2100 J / (kg · K), specific water heat capacity 4200 J / (kg · k).

872. The amount of heat released during condensation of 1 kg of steam at a temperature of 100 ° C and the cooling of the resulting water to 0 ° C is spent on the melting of a certain amount of ice, the temperature of which is 0 ° C. Determine the mass of melting ice. The specific heat capacity of water is 4200 J / (kg × K), the specific heat of water vaporization of 2.22 mJ / kg, the specific heat of melting ice 330 kJ / kg.

873. A mixture consisting of 2.51 kg of ice and 7.53 kg of water at a total temperature of 0 ° C should be heated to a temperature of 50 ° C, passing steam at a temperature of 100 ° C. Determine the amount required for this (in d) steam. The specific heat capacity of water is 4200 J / (kg × K), the specific heat of water vaporization of 2.3 MJ / kg, the specific heat of melting ice 330 kJ / kg.

874. The vessel has some amount of water and the same amount of ice in a state of thermal equilibrium. Through the vessel passes water steam at a temperature of 100 ° C. Find the steady water temperature in the vessel if the mass of the passed steam is equal to the initial mass of water. The specific heat capacity of water is 4200 J / (kg · k), the specific heat of water vaporization of 2.3 MJ / kg, the specific heat of melting ice 330 kJ / kg.

875. From a vessel with a small amount of water at 0 ° C, air is pumped out. At the same time, 6.6 g of water evaporates, and the remaining part freezes. Find a mass (in d) of ice formed. The specific heat of the water vaporization at 0 ° C is 2.5 × 106 J / kg, the specific heat of melting ice is 3.3 × 105 J / kg.

Work of the perfect gas

876. At constant pressure of 3 kPa, the volume of gas increased from 7 l to 12 liters. What kind of work made gas?

877. Expanding in a cylinder with a movable piston at a constant pressure of 100 kPa, gas makes the work of 100 kJ. What magnitude did the volume of gas changed?

878. In the isobaric process at a pressure of 300 kPa, the temperature of the ideal gas increased 3 times. Determine the initial volume (in L) of gas, if during the expansion he made the work of 18 kJ.

879. What kind of work make two piles of some gas when the temperature increases for 10 k? Universal gas constant 8300 J / (kmol × K).

880. With the isobar heating of 2 kg of air, it was performed by 166 kJ. How many degrees was heated air? The molar mass of air is 29 kg / kmol, universal gas constant 8300 J / (kmol × K).

881. The same weights of hydrogen and oxygen are internally heated on the same number of degrees. Molar mass of hydrogen 2 kg / kmol, oxygen 32 kg / kmol. How many times is the work performed by hydrogen, more than oxygen?

882. In the cylinder under the piston there is some weight of the gas at a temperature of 300 K, which occupies 6 liters at a pressure of 0.1 MPa. How many degrees need to cool the gas at constant pressure so that at the same time work is made on its compression, equal to 50 J?

883. In the cylinder with an area of \u200b\u200b100 cm 2 it is gas at a temperature of 300 K. at a height of 30 cm on the base of the cylinder is a piston weighing 60 kg. What kind of work is gas when expanding, if its temperature is slowly increased by 50 ° C? Atmospheric pressure 100 kPa, g. \u003d 10 m / s 2 .

884. In the cylinder under the piston, there is a gas held in the volume of 0.5 m3 of severity of the piston and the force of atmospheric pressure. What kind of work (in KJ) will make gas when heated, if its volume increases by 2 times? The atmospheric pressure of 100 kPa, the mass of the piston is 10 kg, the area of \u200b\u200bthe piston is 10-3 m2. g.\u003d 10 m / s2.

885. One mole of gas is isohoreanly cooled so that its pressure decreased 5 times, and then it washed up to the initial temperature of 400 K. What kind of work made gas? Universal gas constant 8300 J / (kmol × K).

886. Five moles of the gas are first heated at a constant volume so that its pressure increases 3 times, and then compressed at constant pressure, bringing the temperature to the previous value equal to 100 K. What work was performed above the gas when compressing it? Universal gas constant 8300 J / (kmol × K).

887. One mole of perfect gas was cooled from it so that its pressure decreased by 1.5 times, and then heated washed to the previous temperature. At the same time, the gas made a job of 8300 J. Find the initial temperature (in Kelvin) gas. Universal gas constant 8300 J / (kmol × K).