Physical and Chemical Properties

Physical Properties A physical property of a substance is any property of a substance that you can observe without changing it’s identity.

Physical Properties: Appearance Physical properties include how the substance looks These properties include color, shape, size, state of matter (solid, liquid, gas)

Physical Properties: Behavior Physical properties also include how a substance behaves These properties include magnetism, elasticity, ductility, malleability, ability to flow Malleability is the material’s ability to be compressed Ductility is a material’s ability to be stretched

Physical Properties: Touch & Smell Touch and smell are also physical properties of a substance.

Physical Properties: Density Density is the mass of an object divided by its volume D=m/v=g/ml The density of water is 1 g/ml m D v m=Dv D=m/v V=m/D

Physical Change A change is size, shape, or state of matter is a physical change. The identity of the substance remains the same with a physical change.

Using Physical Properties to Separate Mixtures can also be separated by physical properties. Distillation is the process of using heat to remove liquid from a mixture and then recompensing it.

Chemical Properties A chemical property is a characteristic of a substance that indicates whether it can undergo a chemical change. These include reactivity, flammability, stability, and toxicity Reactivity is the ability of a substance to react with another Flammability is the ability of something to burn Stability is a substances tendency not to react Toxicity is the degree to which a substance can damage a living or non-living organisms

Chemical Change During a chemical change, the identity of the substance changes. New substances are formed during a chemical change. Some indicators of a chemical change is a change physical properties Chemical changes can’t be undone by physical changes

Using Chemical Change to Separate Chemical changes can be used to separate things or return them to their original state. An example would be tarnish on silver. This can be turned back into silver through a chemical reaction with aluminum foil, baking soda, and water.

Comparing Chemical & Physical Properties Substance Physical propertyChemical property Helium less dense than airnonflammable Woodgrainy textureflammable Baking sodawhite powder reacts with vinegar to produce bubbles Ironmalleablereacts with oxygen Powdered sugarwhite powderdoes not react with vinegar Rubbing alcoholclear liquidflammable Red food coloringred color reacts with bleach and loses color

Conservation of Mass The law of conservation of mass states that the mass of all of the substances present before a chemical change is equal to the mass of all substances that remain after. Mass of products = mass of reactants