Physical and Chemical Properties
Matter Anything that has mass and takes up space
Physical Properties Any property of matter that can be observed or measured without changing the identity of matter being studied
Physical Properties Typically, physical properties are things that you can detect with your senses (taste, hear, smell, see, or feel) Some physical properties size, mass, volume, length, shape, depend on the amount of substance present
Physical Change Substances are not altered chemically, merely changed to another phase or separated, or combined. Alteration of a substance, but substance remains the same Ex: Water to Ice Whole apple to half apple
Chemical Properties Properties that are measured and observed only during a chemical reaction
Chemical Properties Chemical properties show the potential of matter to go through some chemical changes or reactions can only be observed by changing the identity of the substance.
Chemical Change Substances are altered chemically and display different physical and chemical properties after the change. Two substances interact to form another substance. Ex: water to peroxide
Physical Properties
The rate at which a substance transfers heat Thermal Conductivity The rate at which a substance transfers heat
Magnetism Property of some materials to attract iron or objects containing iron
The ability of a substance to dissolve in another substance Solubility The ability of a substance to dissolve in another substance
State The physical form in which a substance exists, such as a solid, liquid, or gas.
The ability of a substance to be pulled into a wire. Ductility The ability of a substance to be pulled into a wire.
Electrical Conductivity Describes how freely charges can move in a material.
Malleability The ability of a substance to be rolled or pounded into thin sheets.
Melting point The temperature at which a substance changes from a solid to a liquid at a given pressure water = 0oC 32°F
Boiling point The temperature at which a substance changes from a liquid to a gas at a given pressure water = 100oC 212°F
Specific Heat The amount of energy needed to change the temperature of 1 kg of a substance by 1°C
Density Is the mass per unit volume of a substance D=M V
Color Used to identify a substance Observed Absence of color
Identify a substance by the way it smells or does not smell Odor Identify a substance by the way it smells or does not smell
Evidence of Physical Change Change in state Example: Melting of cheese Evaporation of water Sublimation of air freshener Change in size Example Cutting, Tearing, and Breaking Change in shape Example Dissolving, Stretching or Wrinkling
Chemical Properties
Flammability The ability of a substance to burn.
Combustibility Is the amount of energy that is released as heat when a substance is burned with oxygen.
Reactivity The ability of two or more substance to combine and form one or more new substance
Reactivity Oxygen Quickly produce light and heat Slowly produces rust on iron and apples turn brown
Reactivity Acid A substance ability to react with an acid and form a new substance.
Indicators of a chemical change: Evolution of Light Evolution of Heat Temperature Change Evolution of gas Bubbles Color Change Oxygen reacts with iron and turns it red Formation of precipitate 2 solution are added together and form a solid
Indicators of Chemical Change Production of Odor Evolution of Light When through the change in chemical composition a new odor is created. This does not include an odor that is present before any chemical reaction Ex: Perfume When the change in chemical composition produces light Ex: fireworks
Indicators of a Chemical Change Formation of Precipitate Color Change When two or more liquid substances combine sometimes an insoluble solid substance will form. The color of some substance will change when their chemical composition changes. This does not include mixing colors or actual colors.
Indicators of Chemical Change Evolution of Temperature Evolution of Gas Every chemical reaction involves a change in energy/temperature. An endothermic reaction occurs when a substance absorbs heat An exothermic reaction occurs when heat is released. When gas or gas bubbles are seen it means that a new substance has been created. Gas can be above or below the surface of a substance
Examples of a Chemical Changes Burning Digesting food Reacting with other substances A chemical change is called a chemical reaction