States of Matter
The earth is one large mixture of molecules in the solid, liquid and gaseous states.
Matter refers to anything that has mass and takes up space.
Matter has both physical and chemical properties.
Physical Properties
Physical properties can be observed or measured without changing the composition of matter. Physical properties are used to observe and describe matter.
Physical properties include: appearance, texture, color, odor, melting point, boiling point, density, solubility and polarity.
The three states of matter are: solid, liquid, and gas. The melting point and boiling point are related to changes of the state of matter. All matter may exist in any of three physical states of matter.
A physical change takes place without any changes in molecular composition. The same element or compound is present before and after the change. The same molecule is present throughout the changes. Physical changes are related to physical properties since some measurements require that changes be made.
Chemical Properties
Chemical properties of matter describes its "potential" to undergo some chemical change or reaction by virtue of its composition. What elements, electrons, and bonding are present to give the potential for chemical change.
It is quite difficult to define a chemical property without using the word "change". Eventually you should be able to look at the formula of a compound and state some chemical property. At this time this is very difficult to do and you are not expected to be able to do it.
For example hydrogen has the potential to ignite and explode given the right conditions. This is a chemical property.
Chemical change results in one or more substances of entirely different composition from the original substances. The elements and/or compounds at the start of the reaction are rearranged into new product compounds or elements.
A CHEMICAL CHANGE alters the composition of the original matter. Different elements or compounds are present at the end of the chemical change. The atoms in compounds are rearranged to make new and different compounds.
Magnesium reacts with oxygen from the air producing an extremely bright flame. This is a chemical change since magnesium oxide has completely different properties than magnesium metal
There are three main states of matter. They are solid, liquid and gas.
Properties of a solid
1. Particles of a solid are tightly packed, arranged uniformly
2. A solid has a definite volume and definite shape.
Reason: The intermolecular force of attraction is very strong. The molecules are strongly held and arranged in order.
3. A solid is rigid and cannot be compressed easily.
Reason: Molecules are closely spaced and the intermolecular separation is very small which cannot be reduced further.
4. A solid does not flow and can be stored in a container.
Reason: Intermolecular fore of attraction is so strong that molecules do not flow and leave the surface of the solid.
5. A solid on heating usually changes into its liquid state.
Reason: Heating provides sufficient energy to molecules to overcome the intermolecular force of attraction. Intermolecular separation increases, changing the solid into liquid.
Properties of a liquid
1. A liquid has a definite volume.
Reason: Intermolecular force of attraction is just strong enough to confine the molecules in a definite space.
2. A liquid has no definite shape and acquires the shape of the container. It can flow from a higher lever to a lower level.
Reason: Intermolecular force of attraction is weaker in a liquid than in a solid. Liquid molecules can move, slip and slide over each other because their molecular separation is larger. The liquid acquires the shape of the container.
3. Reason: Intermolecular force of attraction is weaker but molecular speed is greater in a liquid than in a solid. The effect of attraction confines the molecules whereas the effect of speed makes the molecules fly apart. The combined effect of these two factors is such that a liquid has a surface which depends on the shape of the container.
4. A liquid is compressible.
Reason: Distance between the neighboring molecules is larger in a liquid than in a solid.
5. A liquid on heating changes into its gaseous state.
Reason: Heating increases the intermolecular separation of the liquid molecules but decreases their intermolecular force of attraction. On cooling, vapours lose heat and are converted into liquid.
Properties of a gas
1. A gas has no definite shape or volume of its own. It acquires the shape of the container.
Reason: Intermolecular attraction is the weakest in gases whereas intermolecular separation is the largest. Hence, molecules in a gas move very fast and the gas expands to fill all the space available.
2. A gas has no surface of its own.
Reason: Molecules escape from an open container.
3. A gas is not rigid and is easily compressed.
Reason: Intermolecular separation is very large in gaseous state which can be decreased by applying pressure.
4. A gas can diffuse into another gas.
Reason: Molecules in a gas move very fast. Hence the speed of diffusion is very large.
5. A gas on cooling changes into liquid state.
Reason: Cooling reduces intermolecular separation and increase intermolecular force of attraction.
The Kinetic Theory of Matter
The Kinetic Theory explains the differences between the three states of matter. It states that all matter is made up of moving particles which are molecules or atoms. In solids, the particles are so tightly bound to each another that they can only vibrate but not move to another location.
In liquids, the particles have enough free space to move about, but they still attract one another. In gases, the particles are far apart and can move about freely since there is much free space. Solids change into liquids, and liquids into gases, when the particles gain more kinetic energy, like when being heated and are able to move apart from one another. When the molecules vibrate more quickly upon heating, some of it escapes from the matter. This is what the Kinetic Theory is about.
1. All matter is composed of small particles.
2. The particles of matter are in constant motion.
3. All collisions between the particles of matter are perfectly elastic
Matter refers to anything that has mass and takes up space.
Matter has both physical and chemical properties.
Physical Properties
Physical properties can be observed or measured without changing the composition of matter. Physical properties are used to observe and describe matter.
Physical properties include: appearance, texture, color, odor, melting point, boiling point, density, solubility and polarity.
The three states of matter are: solid, liquid, and gas. The melting point and boiling point are related to changes of the state of matter. All matter may exist in any of three physical states of matter.
A physical change takes place without any changes in molecular composition. The same element or compound is present before and after the change. The same molecule is present throughout the changes. Physical changes are related to physical properties since some measurements require that changes be made.
Chemical Properties
Chemical properties of matter describes its "potential" to undergo some chemical change or reaction by virtue of its composition. What elements, electrons, and bonding are present to give the potential for chemical change.
It is quite difficult to define a chemical property without using the word "change". Eventually you should be able to look at the formula of a compound and state some chemical property. At this time this is very difficult to do and you are not expected to be able to do it.
For example hydrogen has the potential to ignite and explode given the right conditions. This is a chemical property.
Chemical change results in one or more substances of entirely different composition from the original substances. The elements and/or compounds at the start of the reaction are rearranged into new product compounds or elements.
A CHEMICAL CHANGE alters the composition of the original matter. Different elements or compounds are present at the end of the chemical change. The atoms in compounds are rearranged to make new and different compounds.
Magnesium reacts with oxygen from the air producing an extremely bright flame. This is a chemical change since magnesium oxide has completely different properties than magnesium metal
There are three main states of matter. They are solid, liquid and gas.
Properties of a solid
1. Particles of a solid are tightly packed, arranged uniformly
2. A solid has a definite volume and definite shape.
Reason: The intermolecular force of attraction is very strong. The molecules are strongly held and arranged in order.
3. A solid is rigid and cannot be compressed easily.
Reason: Molecules are closely spaced and the intermolecular separation is very small which cannot be reduced further.
4. A solid does not flow and can be stored in a container.
Reason: Intermolecular fore of attraction is so strong that molecules do not flow and leave the surface of the solid.
5. A solid on heating usually changes into its liquid state.
Reason: Heating provides sufficient energy to molecules to overcome the intermolecular force of attraction. Intermolecular separation increases, changing the solid into liquid.
Properties of a liquid
1. A liquid has a definite volume.
Reason: Intermolecular force of attraction is just strong enough to confine the molecules in a definite space.
2. A liquid has no definite shape and acquires the shape of the container. It can flow from a higher lever to a lower level.
Reason: Intermolecular force of attraction is weaker in a liquid than in a solid. Liquid molecules can move, slip and slide over each other because their molecular separation is larger. The liquid acquires the shape of the container.
3. Reason: Intermolecular force of attraction is weaker but molecular speed is greater in a liquid than in a solid. The effect of attraction confines the molecules whereas the effect of speed makes the molecules fly apart. The combined effect of these two factors is such that a liquid has a surface which depends on the shape of the container.
4. A liquid is compressible.
Reason: Distance between the neighboring molecules is larger in a liquid than in a solid.
5. A liquid on heating changes into its gaseous state.
Reason: Heating increases the intermolecular separation of the liquid molecules but decreases their intermolecular force of attraction. On cooling, vapours lose heat and are converted into liquid.
Properties of a gas
1. A gas has no definite shape or volume of its own. It acquires the shape of the container.
Reason: Intermolecular attraction is the weakest in gases whereas intermolecular separation is the largest. Hence, molecules in a gas move very fast and the gas expands to fill all the space available.
2. A gas has no surface of its own.
Reason: Molecules escape from an open container.
3. A gas is not rigid and is easily compressed.
Reason: Intermolecular separation is very large in gaseous state which can be decreased by applying pressure.
4. A gas can diffuse into another gas.
Reason: Molecules in a gas move very fast. Hence the speed of diffusion is very large.
5. A gas on cooling changes into liquid state.
Reason: Cooling reduces intermolecular separation and increase intermolecular force of attraction.
The Kinetic Theory of Matter
The Kinetic Theory explains the differences between the three states of matter. It states that all matter is made up of moving particles which are molecules or atoms. In solids, the particles are so tightly bound to each another that they can only vibrate but not move to another location.
In liquids, the particles have enough free space to move about, but they still attract one another. In gases, the particles are far apart and can move about freely since there is much free space. Solids change into liquids, and liquids into gases, when the particles gain more kinetic energy, like when being heated and are able to move apart from one another. When the molecules vibrate more quickly upon heating, some of it escapes from the matter. This is what the Kinetic Theory is about.
1. All matter is composed of small particles.
2. The particles of matter are in constant motion.
3. All collisions between the particles of matter are perfectly elastic