Topic 1: Properties and Structure of Matter

1.1 : Properties of Matter

Inquiry question: How do the properties of substances help us to classify and separate them?

1.1.1 : Explore homogeneous mixtures and heterogeneous mixtures through practical investigation

1.1.1.1 : Using separation techniques based on physical properties (ACSCH026)

1.1.1.2 : Calculating percentage composition by weight of component elements and/or compounds (ACSCH007)

There are many ways of calculating the percentage composition of an element, compound and mixture. Gravimetric analysis is a class of lab techniques used to determine the mass or concentration of a substance by measuring a change in mass. It often requires a combination of separating techniques, and for you to measure the weight of all equipment and results carefully. 

1.1.2 : Investigate the nomenclature of inorganic substances using International Union of Pure and Applied Chemistry (IUPAC) naming conventions 

1.1.3 : Classify the elements based on their properties and position in the periodic table 

1.1.3.1 : Physical properties

Physical properties are those that can be found by studying the substance itself (such as appearance, hardness, melting and boiling point, conductivity, malleability, magnetic effects and density). These can be observed or measured without changing the element.

Common physical properties

• Melting and boiling point

• Density

• Electrical conductivity

• Hardness

• Thermal conductivity

• Physical state (solid, liquid, gas)

• Crystalline form

Metals and Non-Metals

The properties that distinguish metals and non-metals are all physical properties.

Metals

• Most metals are solid at room temperature (not Mercury)

• Have a shiny or lustrous appearance

• Are good conductors of electricity and heat

• Are malleable and (able to be rolled into sheets)

• Are ductile ( able to be  drawn into wires)

• Hard with a high density

Non-Metals

• Can be solids or gases at room temperature (except bromine)

• Generally have a dull and non-lustrous appearance (except diamond)

• Non-metals are generally poor conductors of heat and electricity (except graphite)

• Are neither malleable nor ductile, often brittle

• Lower density and melting/boiling point (compared to metals)

• High ionization energies and electronegativity

1.1.3.2 : Chemical properties

Chemical properties describe how a substance reacts (such as whether it reacts with water, whether they are acids or bases, if it is stable or decomposes when heated, whether it is reactive or inert). Since these properties are based on chemical reactions, new products will be formed in the process.

Common chemical properties

• Flammability

• Radioactivity

• Heat of combustion (amount of heat given off when the substance is completely burned)

• Solubility

• Reactivity with water

• Reactivity with acids

• Oxidation (the combination of a substance with oxygen)

• Corrosion (a corrosive substance that will destroy or irreversibly damage another surface)

• Electrode potential

Groups and Periods

The elements that run horizontally are called periods, the elements that run vertically are called groups. Each group has distinctive chemical features and unique valances.