Physics

Thermal Properties of Matter

302 Questions

Thermal properties of matter examine how substances react to heat, covering concepts like temperature, specific heat, and phase changes. This topic is regularly tested in the physics and general science sections of competitive exams. Use this collection to solve numericals on heat transfer, thermal equilibrium, and melting points.

Heat transfer and mixingMelting and freezing pointsThermal expansion and densityTriple point of waterCarnot cycle applications

Thermal Properties of Matter Questions

Multiple choice physics heat and energy zeroth law of thermodynamics

Four cubes of ice at $-10^{o}C$ each one gm is taken out from the refrigerator and are put in $150\ gm$ of water at $20^{o} C$. The temperature of water when thermal equilibrium is attained. Assume that no heat is lost to the outside and water equivalent of container is $46\ gm$. (Specific heat capacity of water $=1\ cal/gm-\ ^{o}C$, Specific heat capacity of fusion of ice $=0.5 cal/gm-\ ^{o}C$, Latent heat of fusion of ice $= 80\ cal/gm$)

  1. $0^{o}C$
  2. $-10^{o}C$
  3. $17.9^{o}C$
  4. $None$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The heat required to warm 4g of ice from -10C to 0C is 20 cal. The heat required to melt 4g of ice is 320 cal. The heat available from 150g of water cooling from 20C to 0C is 3000 cal. Since the available heat is much greater than the heat required to melt the ice, the final temperature will be 0C with some ice remaining.

Multiple choice physics heat and energy zeroth law of thermodynamics

$1\ g$ of ice is mixed with $1\ g$ of steam. At thermal equilibrium, the temperature of the mixture is

  1. $50^{\circ}C$
  2. $0^{\circ}C$
  3. $55^{\circ}C$
  4. $100^{\circ}C$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

1g of steam at 100C releases 540 cal to condense and 100 cal to cool to 0C. 1g of ice at 0C requires 80 cal to melt. The steam has far more energy than needed to melt the ice, so the mixture will reach 100C.

Multiple choice

How does using a metal cookie sheet help with baking holiday cookies?

  1. metal is a good insulator of heat

  2. metal is a good conductor of heat

  3. metal helps block radiation

  4. metal prevents burning
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Metal is a material that allows heat to move through it efficiently, which is the definition of a thermal conductor. This helps bake cookies evenly.

Multiple choice chemistry chemical equilibrium equilibrium in physical processes introduction to equilibrium chemical equilibrium and acids-bases

At 373 K, steam and water are in equilibrium and $\Delta H$ = 40.98 kJ $mol^{-1}$.What will be  $\Delta S$ fro conversion of water into steam?
$H _2O _{(l)} \rightarrow H _2O _{(g)}$

  1. 109.8 J $K^{-1}mol^{-1}$
  2. 31 J $K^{-1}mol^{-1}$
  3. 21.98 J $K^{-1}mol^{-1}$
  4. 326 J $K^{-1}mol^{-1}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The given reaction is :-

${ H } _{ 2 }O\left( l \right) \longrightarrow { H } _{ 2 }O\left( g \right) $
So, we have
       $\triangle Svap=\dfrac { \triangle Hvap }{ Tb } $
                     $=\dfrac { 40.98\times 1000 }{ 373 } =109.8{ JK }^{ -1 }{ mol }^{ -1 }$

Multiple choice chemistry hydroxy compounds and ethers physical properties of phenol physical properties of alcohols and phenols organic compounds with functional group containing oxygen (part-1)

Melting point of phenol is :

  1. $53^0C$
  2. $43^0C$
  3. $33^0C$
  4. $23^0C$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Pure phenols are generally colorless solids or liquids. Phenols (molecular weight $=94$) have the relatively low melting point. So generally exist in liquid form above room temperature.

its melting point is $43^0C$.

Multiple choice physics structure of earth electricity from water energy hydro electricity hydro energy

The minimum height required to convert the stored potential energy of water into electric energy is ____.

  1. $54\ M$
  2. $34\ M$
  3. $100\ M$
  4. $5\ M$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The minimum height required to convent the stored potential energy of water into electric energy is $34\ M$ between the turbine and free energy of water in reservoir.

Multiple choice physics temperature and heat application of various thermometric scales different types of thermometers measuring temperature

On a new scale of temperature (which is linear) and called the W scale, the freezing and boiling points of water are $39^o$W and $239^o$W respectively. What will be the temperature on the new scale, corresponding to a temperature of $39^o$C on the Celsius scale ?

  1. $78^o$W
  2. $117^o$W
  3. $200^o$W
  4. $139^o$W
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The scale is linear: W = m * C + c. 0C = 39W, 100C = 239W. Slope m = (239-39)/100 = 2. W = 2 * C + 39. For C = 39, W = 2 * 39 + 39 = 78 + 39 = 117.

Multiple choice physics energy and its forms introduction to work work introduction to work and energy

Water falls from a height of $210\, m$. Assuming whole of energy due to fall is converted into heat the rise in temperature of water would be 
($J = 4.3$ Joule/cal)

  1. $42^0\, C$
  2. $49^0\, C$
  3. $0.49^0\, C$
  4. $4.9^0\, C$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$\begin{array}{l} \Delta \theta =0.0023h \ =0.0023\times 210 \ ={ 0.483^{ 0 } }C \ =\approx { 0.49^{ 0 } }C \end{array}$

Hence, Option $C$ is correct.

Multiple choice physics kinetic theory of gases thermal expansion in gases thermal expansion of fluids volume elasticity constant of gases

The SI unit for the coefficient of cubical expansion is

  1. $^\circ C$
  2. $per^\circ C$
  3. $cm^{2}/^\circ C$

  4. none of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
The SI unit of coefficient of cubical expansion is $K^{-1}$
$\gamma =\cfrac { 1 }{ V } \cfrac { dV }{ dT } =\cfrac { 1 }{ { metre }^{ 3 } } \cfrac { { metre }^{ 3 } }{ K } ={ K }^{ -1 }$
Multiple choice zoology biodiversity and conservation hotspots and methods of conservation biodiversity: conservation conservation of biodiversity basis of classification in animals basis of the classification of animals criteria for animal classification

Cryopreservation is carried out at

  1. -10 to -20$^{0}$C
  2. -50 to -60$^{0}$C
  3. -196$^{0}$C
  4. -100$^{0}$C
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Cryopreservation is the preservation of cells and tissue by freezing.
Cryopreservation is based on the ability of certain small molecules to enter cells and prevent dehydration and formation of intracellular ice crystals, which can cause cell death and destruction of cell organelles during the freezing process. 
Most systems of cellular cryopreservation use a controlled-rate freezer. This freezing system delivers liquid nitrogen into a closed chamber into which the cell suspension is placed. Careful monitoring of the rate of freezing helps to prevent rapid cellular dehydration and ice-crystal formation. In general, the cells are taken from room temperature to approximately $−190^0$C in a controlled-rate freezer. The frozen cell suspension is then transferred into a liquid-nitrogen freezer maintained at extremely cold temperatures with nitrogen in either the vapour or the liquid phase. Cryopreservation based on freeze-drying does not require use of liquid-nitrogen freezers.
Multiple choice conduction in metals and non-metals thermal energy transfers physics

When a thermometer is taken from the melting ice to a warm liquid, the mercury level rises to two-fifths of the distance between the lower and the upper fixed points. Find the temperature of the liquid $(i)i{n^o}C,and(ii)\;in\;K.$ 

  1. ${40^0}C.313K$
  2. ${30^0}C.227K$
  3. ${20^0}C.273K$
  4. ${0^0}C.0K$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Celsius scale has 100 divisions between 0 and 100. Two-fifths of 100 is 40 degrees Celsius. Converting to Kelvin, 40 + 273.15 = 313.15 K, which rounds to 313 K.