A piston filled with 0.04 mol of an ideal gas expands reversibly from 50.0 mL to 375 mL at a constant temperature of 3 7 . 0 ∘ C . As it does so, it absorbs 208 J of heat. The values of q and w for the process will be (R = 8.314 J/mol K) (ln7.5 = 2.01)

q = + 2 0 8 J , w ⁡ = - 2 0 8 J

q = + 2 0 8 J , w ⁡ = + 2 0 8 J

q = - 2 0 8 J , w ⁡ = - 2 0 8 J

Ice water and steam are three statesof a substance and not different substance Justify

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

The work done during combustion of

9 \times 10^{- 2}

kg

of ethane,

C_{2} H_{6} (g)

at

300 K

is (Given

R = 8 .314 {JK}^{- 1} {mol}^{- 1}

, atomic mass

C = 12, H = 1

)

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

The above

P - V

diagram represents the thermodynamic cycle of an engine, operating with an ideal mono-atomic gas. The amount of heat, extracted from the source in a single cycle, is:

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A system consisting of 1 mol of an ideal gas undergoes a reversible process,

A \to B \to C \to A

(schematically indicated in the figure below). If the temperature at the starting point A is 300 K and the work done in the process

B \to C

is 1 L atm, the heat exchanged in the entire process in L atm is

Question Image

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A gas undergoes change from state

A

to state

B

. In this process, the heat absorbed and work done by the gas is

5 J and 8 J

, respectively. Now gas is brought back to

A

by another process during which

3 J

of heat is evolved. In this reverse process of

B to A

.

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

The qualitative sketches I, II and III given below show the variation of surface tension with molar concentration of three different aqueous solutions of KCl,

C H_{3} O H

and

C H_{3} {(C H_{2})}_{11} O S O_{3}^{-} N a^{+}

at room temperature. The correct assignment of the sketches is -

Question Image

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

X g

of ice at

0^{o} C

is added to 340g of water at

20^{o} C

. The final temperature of the resultant mixture is

5^{o} C

. The value of

X

(in g) is closest to

[Heat of fusion of ice

= 333 J / g

; Specific heat of water

= 4.184 J / g . K

]

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A piston filled with 0.04 mol of an ideal gas expands reversibly from 50.0 mL to 375 mL at a constant temperature of

37 . 0^{\circ} C

. As it does so, it absorbs 208 J of heat. The values of q and w for the process will be
(R = 8.314 J/mol K) (ln7.5 = 2.01)

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

The volume vs. temperature graph of 1 mole of an ideal gas is given below

Question Image

The pressure of the gas (in atm) at

X, Y

and

Z,

respectively, are

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

An ideal gas undergoes isothermal compression from

5 m^{3}

to

1 m^{3}

against a constant external pressure of

4 N m^{- 2}

. The heat released in this process is

24 J {mol}^{- 1} K^{- 1}

and is used to increase the pressure of

1

mole of

Al

. The temperature of

Al

increases by:

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

The combination of plots which does not represent isothermal expansion of an ideal gas is

$(A)$ Question Image

$(B)$

$(C)$

$(D)$

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

An ideal gas undergoes isothermal expansion at constant pressure. During the process:

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

"Complete melting of ice cream will not happen suddenly". Explain.

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

For the isothermal reversible expansion of an ideal gas

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

Calculate the work done during compression of

2

mol of an ideal gas from a volume of

1 m^{3}

to

10

{dm}^{3}

at

300 K

against a pressure of

100 kPa

.

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A gas is allowed to expand in a well-insulated container against a constant external pressure of

2.5 atm

from an initial volume of

2.50 L

to a final volume of

4.50 L .

The change in internal energy

ΔU

of the gas in joules will be

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

The molar enthalpy change for

H_{2} O (l) ⇌ H_{2} O (g)

at

373 K

and

1 atm

is

40 kJ / mol

. Assuming ideal behaviour, the internal energy change for vaporization of

1 mol

of water at

373 K

and

1 atm

in

kJ {mol}^{- 1}

is:

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

The three processes in a thermodynamic cycle shown in the figure are : Process $1 \to 2$ is isothermal; Process $2 \to 3$ is isochoric (volume remains constant); Process $1 \to 3$ is adiabatic.

Question Image

The total work done by the ideal gas in this cycle is, $10 J .$ The internal energy decreases by, $20 J$ in the isochoric process. The work done by the gas in the adiabatic process is, $- 20 J$ . The heat added to the system in the isothermal process is

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A reversible cyclic process for an ideal gas is shown below. Here,

P, V, a n d T

are pressure, volume and temperature, respectively. The thermodynamic parameters

q, w, H a n d U

are heat, work, enthalpy and internal energy, respectively.

Question Image

The correct option(s) is (are)

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

A piece of ice falls from a height

h

so that it melts completely. Only one-quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of

h

is:
(Latent heat of ice is

3.4 \times 10^{5} {J kg}^{- 1}

and

g = 10 {N kg}^{- 1}

)

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Physical Sciences>Matter and Its Interactions>Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.>Structure and Properties of Matter - Gases and liquids are made of molecules or inert atoms that are moving about relative to each other

The melting point of naphthalene is

80 ° C

and the room temperature is

30 ° C

. A sample of liquid naphthalene at

100 ° C

is cooled down to the room temperature. Draw a temperature time graph to represent this cooling. In the graph, mark the region which corresponds to the freezing process.

Ice, water and steam are three states of a substance and not different substance. Justify ?

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