Physical and Chemical Properties
By: Elaina Allen
Physical and Chemical Properties
Physical properties are properties that can be observed or measured without changing the composition of matter. It is used to observe and describe matter. For example, texture, color, odor, and melting and boiling point. Chemical properties are a property that describes the composition of matter, the character traits of matter, and the potential of matter to react in a particular way. For example, Hydrogen has potential to explode, metals can react with acid, reactivity with water, flamability, and toxicity.
Physical and Chemical Change
Physical Changes are changes that take place without any changes in molecular composition. The same element or compounds are present before and after the change. The same molecule is also present throughout the changes. Physical changes are related to physical properties since some measurments require that changes be made. For example, crumpling a piece of paper, melting and ice cube, casting silver in a mold, breaking a bottle. Chemical change is the result of a reaction which creates one of more substances with different chemical properties. For example, burning wood, dissolving salt in water, mixing acid and base, and digesting food.
Chemical Reactions
Chemical reactions are a process involving changes to substances; a process that changes the molecular composition of a substance by redistributing atoms or groups of atoms without altering the structure of the nuclei of the atoms. For example, explosion of fireworks, color changes, energy absorbed or released, odor changes. In a chemical reaction, substances are called reactants, are changed to products. For example, the experiment we did, Poly A plus Poly B equals Polyurethane foam.
Law of Conservation Mass
The law of conservation mass is a group of laws on the physical properties of matter, mass, and energy. It says matter can NOT be created OR destroyed.