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Why latent heat is needed to change substance from solid to liquid?
Wiki User
∙ 11y ago
Latent heat is required to be input to turn a solid to a liquid, or a liquid to a gas, and the reverse is true the other way. Thus when water is evaporated to water vapor, a fixed amount of heat must be supplied per kg of water evaporated, and similarly when water vapor condenses, the same amount of heat per kg is released. You can look up values of latent heat per kg in reference tables for different substances.
Specific heat is not relevant to the phase change itself, as the phase change is isothermal (ie at a constant temperature). Specific heat is a way of defining for a substance how much heat is needed to change its temperature by one degree, relative to water which has a specific heat of 1, because we define the heat unit, calorie, as the heat required to raise 1 gram of water by 1 degC. Thus for other substances you take the specific heat (which will be quoted as a number relative to 1) and multiply by the change in temperature and the mass of substance to get the heat quantity in calories. Note that in SI units you will use kilograms rather than grams, the answer will then be in kilocalories which is a more useful quantity. In nutrition, when 'calories' are quoted, these are in fact kilocalories.
Wiki User
∙ 15y ago
Wiki User
∙ 11y agoIn any solid substance, there are chemical bonds between the atoms and molecules of which the substance is composed, that hold it together. In order to make this solid into a liquid, you have to break those bonds, and that requires energy, which is the latent heat.
Wiki User
∙ 12y agoLatent heat is the energy that is required to be put in to (or taken out of) a system of a certain mass, to make a change of state in the system.
It is defined as L = Q/M, where Q is the energy required and M the mass being heated.
Wiki User
∙ 12y agoyes, at melting point or boiling point. Latent heat is the heat where the temperature remains constant but there is a change in state. For example, when water boils, water continues to gain heat but the temperature remains constant. This is called the latent heat of vaporization.
Wiki User
∙ 11y agoto break the bonds between compounds as the matter of the solids are hardly packed...
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Latent heat is the energy required for 1 kg of a substance to change?
Latent heat is the energy required for 1 kg of a substance to change ___________. phase
What is the difference between heat of fusion and heat of vaporization?
Latent heat is the amount of thermal energy required to change the phase of a substance. Latent heat of fusion is the amount of energy needed to change it from a solid to liquid or a liquid to solid, and the latent heat of vaporization is the thermal energy needed to change from a liquid to gas or a gas to liquid. For example, in the equation Q = mL, Lfusion (latent heat of fusion) for water is 75.5 cal/gram. Lvaporization (latent heat of vaporization) for water is 539 cal/gram. Substances have different latent heats.
What is the heat energy needed to change a liquid to gas while the temperature stays the same?
(latent) heat of vaporization
What information does the latent heat of vaporization give?
The energy needed to completely vaporize a mole of a liquid
What energy is needed to change a material from solid to liquid?
Heat energy, usually. However, some substances will change states under the influence of UV or other radiation.AnswerThe energy needed to change a material from a solid to a liquid is called the 'latent heat of fusion', or just the 'heat of fusion'. It is equal to the amount of energy or heat given off by the same material to change it from a liquid back into a solid.Each material has its own heat of fusion. Take solid water (ice) at 0o Celsius, the freezing point. Water's heat of fusion is 79.71 calories per gram. That means that you will need to add 79.71 calories of heat to each gram of ice (solid water) to turn it into liquid water. Interestingly, once that's done, the water will still be at 0o Celsius! The heat was used just to change the water's state from solid to liquid. Once the ice is liquid, then any more heat added will increase the temperature of the liquid, and each calorie of heat will increase the water's temperature about 1o Celsius.This is a similar concept to a material's 'heat of vaporization', which is the amount of energy required to change a liquid to a gas.The amount of heat necessary to change a substance from a solid to a liquid or vice versa is commonly called the heat of fusion. It is more properly known as the standard enthalpy of fusion, or also the latent heat of fusion, or the enthalpy change of fusion. The specific temperature at which the change occurs is defined as the melting point of that substance. A link can be found below.The amount of energy a substance must absorb in order to change from a solid to a liquid is the heat of fusion. A change in which a system absorbs energy from its surroundings is endothermic change.
Latent heat is the energy required for 1 kg of a substance to change?
Latent heat is the energy required for 1 kg of a substance to change ___________. phase
Energy needed to change a material from solid to liquid?
It is the latent heat of liquefaction.
What are the factors that affect specific latent heat of fusion of a substance?
The amount of energy needed to change the "state of matter" is termed as "latent heat". This is not same for vapourisation (liquid to vapour) or for fusion (solid to liquid). For example, latent of fusion is 79.7 cal whereas latent heat for vapourisation is 541 calories. The latent depends on how closely the atoms and molecules in the matter are closely packed.
What is the name of the energy needed to change a substance from a liquid to a gas?
The energy needed to change a substance from a liquid to a gas is called the enthalpy (or heat) of vaporization.
What does the latent heat of vaporization represent?
The amount of energy required to turn a mole of a liquid into a gas
What is the name of heat energy that changes ice into water and water into steam?
Latent heat is the measurement of energy needed to change the state of a substance at its melting point or boiling point. The latent heat of fusion of water is the amount of energy needed to change a fixed amount of water from a solid to liquid at 0 degrees C. this works out to be more than 800KJ of heat energy. The latent heat of vaporization of water is the amount of energy needed to change a fixed amount of water from a liquid to a gas at 100 degrees C. this is more than 1200KJ of heat needed to be absorbed.
What is the difference between heat of fusion and heat of vaporization?
Latent heat is the amount of thermal energy required to change the phase of a substance. Latent heat of fusion is the amount of energy needed to change it from a solid to liquid or a liquid to solid, and the latent heat of vaporization is the thermal energy needed to change from a liquid to gas or a gas to liquid. For example, in the equation Q = mL, Lfusion (latent heat of fusion) for water is 75.5 cal/gram. Lvaporization (latent heat of vaporization) for water is 539 cal/gram. Substances have different latent heats.
What is the definition for latent heat of melting?
The amount of heat released / absorbed from a substance at constant temperature as you change state from liquid->solid / solid->liquid.
What is the heat energy needed to change a liquid to gas while the temperature stays the same?
(latent) heat of vaporization
What is the amount of heat needed to change 1 kg of a specific material from liquid to vapor at a constant temperature?
Latent
What is the energy needed for a substance to change from a liquid state to a gaseous state?
thermol
Why is heat energy needed to melt a solid. What is this heat energy called?
the energy that goes into changing a substance from a solid to a liquid (melting) is called the latent heat of fusion.
