Question

write a brief note on characteristics of substances​

Answer 1

CHARACTERISTICS OF SUBSTANCES:

The characteristic properties of a substance are always the same whether the sample being observed is large or small.

Examples of characteristic properties include freezing/melting point, boiling/condensing point, density, viscosity, and solubility.

Answer 2

Substance is a form of matter that has constant chemical composition and characteristic properties.

Explanation:

• A chemical substance is a form of matter that has constant chemical composition and characteristic properties.

• It cannot be separated into components without breaking chemical bonds.

• Chemical substances can be solids, liquids, gases, or plasma.

• Changes in temperature or pressure can cause substances to shift between the different phases of matter.

• The characteristics that enable us to distinguish one substance from another are called properties. These properties are mainly classified as physical property and chemical property.

Physical Property

• A physical property is a characteristic of matter that is not associated with a change in its chemical composition.

• Examples of physical properties include density, colour, hardness, melting and boiling points, and electrical conductivity.

• Other physical properties such as the melting temperature of iron or the freezing temperature of water, can be observed as matter undergoes a physical change.

• A physical change is a change in the state or properties of matter without any accompanying change in its chemical composition.

Chemical Property

• The change of one type of matter into another type or the inability to change is a chemical property.

• Examples of chemical properties include flammability, toxicity, acidity, reactivity and heat of combustion.

• A chemical change always produces one or more types of matter that differ from the matter present before the change.

• The formation of rust is a chemical change because rust is a different kind of matter than the iron, oxygen, and water present before the rust formed.