Description : Steam at 100°C causes more severe burns than water at 100° C because – (1) steam has no specific heat capacity (2) steam has latent heat of vaporization (3) water has no specific heat capacity (4) water has latent heat of fusion
Last Answer : (2) steam has latent heat of vaporization Explanation: It is because steam releases its latent heat as it condenses, which is substantial. The heat of vaporization of steam is over 2000 J per gram. And when it releases that it's then 100 degree water, the same as boiling water.
Description : Burns caused by steam are much severe than those caused by boiling water because – (1) Steam pierces through the pores of body quickly (2) Steam has latent heat (3) Steam is gas and engulfs the body quickly (4) Temperature of steam is higher
Last Answer : (2) Steam has latent heat Explanation: When water changes into steam, it absorbs latent heat, and when steam condenses to form water, it gives out an equal amount of latent heat. Bums caused ... boiling water, simply because steam contains more heat (in the form of latent heat) than boiling water.
Description : Burns caused by steam are much severe than those caused by boiling water because (1) Steam pierces through the pores of body quickly (2) Steam has latent heat (3) Steam is gas and engulfs the body quickly (4) Temperature of steam is higher
Last Answer : Steam has latent heat
Description : The snow on the mountains does NOT melt all at once when it is heated by the sum because: (1) It becomes very hard (2) It reflects most of the heat from the sum (3) it has a low specific heat capacity (4) it has a high latent heat of fusion
Last Answer : (2) It reflects most of the heat from the sum Explanation: Newly formed snow reflects about 90 per cent of the sunlight that falls upon it. This means that the sun is powerless to melt clean snow. And when ... on a spring day because of the sun's heat. It melts because of the warm air from the sea.
Description : The snow on the mountains does NOT melt all at once when it is heated by the sun because: (1) it becomes very hard (2) it reflects most of the heat from the sun (3) it has a low specific heat capacity (4) it has a high latent heat of fusion
Last Answer : it reflects most of the heat from the sun
Description : The snow on the mountains does not melt all at once when it is heated by the sun because _____ A. It becomes very hard It B. It reflects most of the heat from the sun C. It has a low specific heat capacity D. It has a high latent heat of fusion
Last Answer : ANSWER: B
Description : The critical pressure at which the latent heat of vaporisation of steam becomes zero is __________ Kg/cm2. (A) 273.15 (B) 225.65 (C) 100.03 (D) 373.15
Last Answer : (B) 225.65
Description : The ______ of a substance is the amount of heat that must be added or removed from a unit mass of the substance to change its temperature by one degree. A. Latent heat of fusion B. Molar heat C. Specific heat capacity D. Specific heat
Last Answer : Specific heat capacity
Description : What is defined as the energy required to raise the temperature of a unit mass of a substance by one degree? A. Latent heat of fusion B. Molar heat C. Specific heat capacity D. Specific heat
Last Answer : Specific heat
Description : Gibbs free energy per mole for a pure substance is equal to the (A) Latent heat of vaporisation (B) Chemical potential (C) Molal boiling point (D) Heat capacity
Last Answer : (B) Chemical potential
Description : It is desired to concentrate a 20% salt solution (20 kg of salt in 100 kg of solution) to a 30% salt solution in an evaporator. Consider a feed of 300 kg/min at 30°C. The boiling point of the solution is 110°C, the latent heat of ... 3.06 10 5 (B) 6.12 10 5 (C) 7.24 10 5 (D) 9.08 10
Last Answer : (A) 3.06 × 10
Description : High __________ is an undesirable property for a good refrigerant. (A) Specific heat (B) Latent heat of vaporisation (C) Viscosity (D) Specific vapor volume
Last Answer : (C) Viscosity
Description : Heat which causes a change in temperature of a substance. a. Latent heat b. Sensible heat c. Specific heat d. Heat of Fusion
Last Answer : Sensible heat
Description : Pick out the wrong statement. (A) Bubble size increases with the dynamic viscosity of the liquid in case of nucleate pool boiling (B) Thermal conductivity of a dry material is more than ... in kg/hr in an evaporator (D) Vaporisation of organic substances in evaporator mostly causes foam formation
Last Answer : (B) Thermal conductivity of a dry material is more than that of the damp material
Description : The solvent used in liquid extraction should not have high latent heat of vaporisation, because (A) The pressure drop and hence the pumping cost will be very high (B) It cannot ... by distillation may be prohibitively high (D) It will decompose while recovering by distillation
Last Answer : (C) Its recovery cost by distillation may be prohibitively high
Description : Which of the following produces more severe burns? (1) Boiling water (2) Hot water (3) Steam (4) Melting Iceberg
Last Answer : (3) Steam Explanation: A burn is an injury to the body's tissue resulting from heat, chemicals, electricity or sunlight. Burns are often classified as first degree (those causing damage to the ... deepest and most severe damage destruction of all layers of the skin and damage to tissues underneath.
Description : Which of the following produces more severe burns ? (1) Boiling water (2) Hot water (3) Steam (4) Melting iceberg
Last Answer : Steam
Description : Burns caused by steam are much more severe than those caused by boiling water because
Description : Which of the following cannot be measured by a thermometer? a. Latent Heat b. Sensible Heat c. Specific Heat d. Heat of Fusion
Last Answer : Latent Heat
Description : In distillation column design, the McCabe-Thiele procedure is inadequate and a Ponchan-Savarit procedure is needed, when (A) Saturated feed is not used (B) An azeotrope forms (C) The latent ... vaporisation of the more and less volatile components are greatly different (D) A total condenser is used
Last Answer : (D) A total condenser is used
Description : In a cooling tower, water becomes cool by (A) Loosing sensible heat (B) Heat transfer to surroundings (C) Vaporisation due to heat loss to air (D) Loosing latent heat
Last Answer : (A) Loosing sensible heat
Description : Why high latent heat of vaporisation is desirable in a refrigerant ?
Last Answer : A high latent heat of vaporisation of refrigerant results in small amount of refrigerant and thus lesser circulation system of refrigerant for same tonnage.
Description : Entrainer used in Azeotropic distillation should (A) Form a low boiling azeotrope with one of the constituents of the mixture (B) Form a new azeotrope of low relative volatility with one of the ... (C) Have high latent heat of vaporisation (D) Have high viscosity to provide high tray efficiency
Last Answer : (A) Form a low boiling azeotrope with one of the constituents of the mixture
Description : Heat sensitive materials with very high latent heat of vaporisation may be economically separated using (A) Liquid extraction (B) Distillation (C) Evaporation (D) Absorption
Last Answer : (A) Liquid extraction
Description : When the solvent dissolves very little of solute, then (A) Solvent of low latent heat of vaporisation should be used (B) Solvent of low freezing point should be used (C) Large quantity of solvent is required to extract the solute (D) Very small quantity of solvent is required
Last Answer : (C) Large quantity of solvent is required to extract the solute
Description : An equipment which converts the latent or sensible heat of one fluid into the latent heat of vaporisation of another, is called a (A) Boiler (B) Heat exchanger (C) Recuperator (D) Regenerato
Last Answer : (B) Heat exchanger
Description : Clausius-Clapeyron Equation gives accurate result, when the (A) Vapour pressure is relatively low and the temperature does not vary over wide limits (B) Vapour obeys the ideal gas law and the latent heat of ... is negligible compared with that in the vapour state (D) All (A), (B) and (C)
Last Answer : (D) All (A), (B) and (C)
Description : ick out the undesirable property for a good refrigerant. (A) High thermal conductivity (B) Low freezing point (C) Large latent heat of vaporisation (D) High viscosity
Last Answer : (D) High viscosity
Description : Why does steam cause more severe burns than boiling water?
Last Answer : Ans: The amount of heat (latent heat) possessed by steam is much greater than the amount of heat possessed by water at the same temperature. Therefore, steam causes more severe burns than boiling water
Description : Water is not suitable as a calorimetric substance because it – (1) has high specific heat (2) is a good conductor (3) has high boiling point (4) low latent heat of vaporization
Last Answer : (1) has high specific heat Explanation: The specific heat of water is higher than all other common substances. Hence, water is used for heating purposes (as in hot water bottles) and for cooling ... the liquids, mercury has the lowest specific heat due to which it is used as a thermometric liquid.
Description : Water is not suitable as a calorimetric substance because it : (1) has high specific heat (2) is a good conductor (3) has high boiling point (4) low latent heat of vapourization
Last Answer : has high specific heat
Description : steam distillation, the (A) Temperature is 100°C(B) Temperature is more than 100° C (C) Product must be immiscible with water (D) Temperature is higher than the boiling point of either component
Last Answer : (C) Product must be immiscible with water
Description : Heat evolved/absorbed during conversion of a substance from one allotropic form to another is termed as the heat of (A) Fusion (B) Vaporisation (C) Transition (D) None of these
Last Answer : (C) Transition
Description : Absorption/evolution of heat during conversion of a substance from one allotropic form to another is termed as the heat of (A) Sublimation (B) Fusion (C) Transition (D) Vaporisation
Last Answer : C) Transition
Description : The number of kg vaporised per kg of steam fed to the evaporator is defined as (A) Capacity (B) Rate of evaporation (C) Economy (D) Rate of vaporisation
Last Answer : (C) Economy
Description : At what temperature a body will not radiate any heat energy? (1) 0° C (2) 273° C (3) 100° C (4) -273° C
Last Answer : (4) -273° C
Description : The heat Q per unit mass per degree change in temperature that must be supplied or removed to change the temperature of a substance. a. Specific Heat Capacity b. Latent Heat c. Heat of Transformation d. Internal Heat
Last Answer : Specific Heat Capacity
Description : What is the heat capacity of one gram of a substance? A. Molecular heat B. Specific heat C. Latent heat D. Molar heat
Description : What is the heat capacity of one mole of substance? A. Molecular heat B. Specific heat C. Latent heat D. Molar heat
Last Answer : Molar heat
Description : What refers to the amount of heat needed to raise the temperature of an object by one degree Celsius or 1K? A. Heat capacity B. Specific heat C. Latent heat D. Molar heat
Last Answer : Heat capacity
Description : The quantity of heat required to raise the temperature of a given substance by 1 oC is known as: a) sensible heat b) specific heat c) heat capacity d) latent heat
Last Answer : specific heat specific heat is the quantity of heat required to raise the temperature of 1 gram substance by 1 oC is
Description : What is the latent heat of fusion of water at 1 atm? A. 331.1 kJ/kg B. 332.6 kJ/kg C. 333.7 kJ/kg D. 330.7 kJ/kg
Last Answer : 333.7 kJ/kg
Description : Define latent heat of fusion. Also write its SI unit. -Maths 9th
Last Answer : The SI unit of latent heat is Joule. ... Latent heat is defined as the heat required for converting solid into a liquid or to vapour without any change in the temperature.
Description : How does the latent heat of fusion measure?
Last Answer : The energy required to melt a substance
Description : What is the latent of heat fusion?
Last Answer : The amount of energy it takes to boil a substance
Description : If the vapour pressure at two temperatures of a solid phase in equilibrium with its liquid phase are known, then the latent heat of fusion can be calculated by the (A) Maxwell's equation (B) Clausius-Clapeyron Equation (C) Van Laar equation (D) Nernst Heat Theorem
Last Answer : B) Clausius-Clapeyron Equation
Description : The heat absorbed by a unit mass of a material at its holding point in order to convert the material into a gas at the same temperature. a. Latent Heat of Sublimation b. Latent Heat of Vaporization c. Latent Heat of Fusion d. Latent Heat Of Condensation
Last Answer : Latent Heat of Vaporization
Description : 2000 kJ of heat is supplied to 500 kg of ice at 0oC. If the latent heat of fusion of ice is 335 kJ/kg then the amount of ice in kg melted will be a) 1.49 b) 83.75 c) 5.97 d) None of the above
Last Answer : c) 5.97
Description : Heat stored in water vapour is – (1) specific heat (2) latent heat (3) absolute heat (4) relative heat
Last Answer : (2) latent heat Explanation: Latent heat is the heat released or absorbed by a body or a thermodynamic system during a process that occurs without a change in temperature. A typical example is a ... the boiling of water. So water vapor which is the end product of evaporated water has latent heat.