sugar heated in a saucepan to make caramel.For example, iron objects turn reddish-brown (known as rusting) when exposed to moist air for a long period is a chemical change because iron combines with oxygen and moisture from the air to form a new substance, rust. It involves the formation of new substances that have different properties compared to the original substance. For example, the melting of ice to give water is a physical change because water only changes its physical state from solid to liquid without affecting its chemical identity.Ī chemical change is a process in which the substance changes its chemical identity or composition. Properties of matter Are the properties observed/measured without changing the chemical identity of the substance?įlammability - when wood burns it changes to ashesĬorrosion - rusting of iron objects after exposure to moist air for a long timeĭecomposition - hydrogen peroxide decomposes into water and oxygen in the presence of heat or lightĬhanges in the matter are classified into two categories: physical change and chemical change.Ī physical change is when the substance changes its physical appearance or state without affecting the chemical identity. Properties of matter can be classified into two types depending on whether the particular property is determined by changing the chemical identity or composition of the substance. The change of gas to liquid is known as condensation.The change of liquid to solid is known as freezing.The change of solid to gas is known as sublimation.The change of gas to solid is known as deposition.The change of liquid to gas is known as vaporization.The change of solid to liquid is known as melting. State changes have different names depending on which states are involved: Water is one of the few substances which can exist in all three states: solid ice, liquid water, gaseous steam. The conversion of a substance from one state to another is known as the change of state.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |