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What heat is absorbed or released when a substance changes states?
Wiki User
∙ 14y ago
absorbed: endothermic
released: exothermic
however, substances rarely do this when changing state ()i.e solid to liquid etc()
but it is common in chemical reactions ()Lithium+water for example()
Wiki User
∙ 14y ago
Wiki User
∙ 12y agoYou would use the following equation: q = C x m x (Tf - Ti), where q is heat absorbed or released, C is specific heat, m is mass in grams, and (Tf - Ti) is change in temperature (Tf = final temp, Ti = initial temp).
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What do you call the change in state of matter from a liquid to a gas?
Condensation
When heat is absorbed is it a chemical change?
No. Rather released. As during the physical changes in the states of matter, there is breaking of bonds involved. Whenever bonds are broken, the atoms of that matter come closer and energy they give out is more as compared to energy taken while breaking bonds. Hence, Physical changes at the level of states of Matter are always Exothermic i.e. RELEASING HEAT.
What happens to molecular energy when a substance changes states?
The molecular energy will usually increase or decrease, depending on the exact situation.
What kind of change happens when the composition of a substance does not change?
Physical changes, such as the change from ice to water to steam; the compound remains as H2O in all three states.
Does a change in state mean that a new substance has formed?
In a "physical change" a new substance is not created. In a "chemical change" a new substance is created. This applies to changes in states of matter. For example, ice, water, and steam are all the same substance, even though they exist in three different states. The elements of which they are comprised do not change. Sometimes you may be able to precipitate elements out of a substance through a phase change. In a mixture of alcohol and water you can fairly quickly boil out the alcohol.
What happens when a substance change states?
When a substance changes state, Energy within the substance is gained or lost, but the composition is unchanged.
When a substance changes states at different temperature and pressure this is called?
pasterisation
What does light rays refracted by a concave lens do?
changes in a physical states of a substance is called physical changes.
Are changes in the state of matter are physical chemical or neither?
changes in states of matter are physical changes, as they do not affect the chemical properties of the substance
What change is melting consider because energy is gained by the substance as it changes states?
Melting is a phase change in which a substance changes from the solid state to the liquid state. Changing phases is also a physical change.
What do you call the change in state of matter from a liquid to a gas?
Condensation
When heat is absorbed is it a chemical change?
No. Rather released. As during the physical changes in the states of matter, there is breaking of bonds involved. Whenever bonds are broken, the atoms of that matter come closer and energy they give out is more as compared to energy taken while breaking bonds. Hence, Physical changes at the level of states of Matter are always Exothermic i.e. RELEASING HEAT.
Is the solid state of water a Physical property or a chemical property?
When a substance changes states the chemical make-up of the substance is still the same, so the state of the substance would be a physical property.
Are the atoms in a substance the same if the substance changes states?
On heating there will be a change in the physical state not chemical composition. So the number of atoms will be the same even after change in state.
What happens to molecular energy when a substance changes states?
The molecular energy will usually increase or decrease, depending on the exact situation.
What are some things that have melting points?
All substances have a melting point.Water, for example, has a melting point. It is simply the temperature at which a substance changes states to a liquid.
What are changes in state?
In general, changes of state refer to the physical (as opposed to the chemical) changes of a substance from a solid to a liquid, a liquid to a gas, a gas to a liquid, a solid to a gas, or a gas to a solid. We might do well to consider the situation for a most familiar substance we call water.We know the solid form of water as ice, and steam or water vapor is the gaseous state of this ubiquitous substance. Energy must be added to separate the particles (molecules) of water as ice melts. Said another way, there is more energy in a given mass of liquid water at 0°C as in the same mass of ice at 0°C.The same amount of energy is released when the same amount of water freezes as when it melts. And the same amount of energy is absorbed when water vaporizes, as is released when the water vapor condenses into a liquid.The changes of state are those transitions between the forms of matter we generally recognize. These are solids, liquids and gases. Certainly there are Bose-Einstein condensates (at the "colder" end of the thermal spectrum) and plasmas (at the upper end of the thermal spectrum), but we need to focus on the "basic" states of matter when we consider changes in state.
