Atoms, Elements, Compounds & Mixtures

Vocabulary flashcards covering the definitions, examples, and properties of atoms, elements, compounds, mixtures, and alloys based on the lecture notes.

Atom

The smallest unit of an element that can exist and the fundamental units that make up everything around us.

Element

A substance made up of one type of atom, which can exist in solid, liquid, or gaseous states.

Sodium ($Na$)

An element made up of only sodium atoms.

Hydrogen ($H_2$)

An element made up of only hydrogen atoms.

Metals and Non-Metals

The two divisions of elements in the Periodic Table; metals are found on the left of the stepped line and non-metals on the right.

Compound

A substance made up of two or more different atoms that are chemically bonded together, such as water ($H_2O$) or carbon dioxide ($CO_2$).

Mixture

When two or more substances are physically combined and can be separated by physical methods, such as salt and water or sand and sugar.

Solution

A mixture containing a solute and a solvent.

Solute

The substance in a solution that is being dissolved.

Solvent

The substance in a solution that dissolves the solute, such as water or ethanol.

Chemical Properties

Characteristics used to identify substances including reactivity (vigorous or slow), what it can react with (water or acid), and the formation of coloured compounds.

Physical Properties

Characteristics used to identify substances including appearance (colour, shininess, or dullness), state at room temperature ($s/l/g$), and melting and boiling points.

Magnesium metal ($Mg$)

An element that is a shiny grey solid at room temperature, is malleable, and reacts with acid to form hydrogen gas.

Magnesium carbonate ($MgCO_3$)

A compound that is a white powder and reacts with acid to form carbon dioxide.

Alloy

A mixture of two or more metals.

Properties of Alloys

These substances are harder than their pure metals because it is harder for particles to slide over each other, and they have different chemical and physical properties from their constituent elements.

Bronze

An alloy composed of copper and tin, often used for bells and cymbals.

Brass

An alloy composed of copper and zinc, used for electric plugs and ornaments.

Steel

An alloy composed of iron and carbon, commonly used for car bodies.

Stainless steel

An alloy composed of iron, nickel, and chromium, used for kitchen sinks, knives, forks, and spoons.