Chemistry Module 1 and Module 2 Concepts

Vocabulary practice flashcards covering fundamental chemistry concepts from Module 1 and Module 2 lecture notes, including properties of matter, mixtures, separation techniques, quantitative chemistry, stoichiometry, concentration, and chemical reaction types.

Pure Substance

A form of matter that contains only one element or compound, such as pure water.

Mixture

A physical combination of two or more elements or compounds, such as saltwater.

Homogeneous Mixture

A mixture that is uniform in composition throughout, such as air.

Heterogeneous Mixture

A mixture in which the composition varies throughout, such as blood.

Filtration

A separation technique that separates insoluble solids from liquids by passing them through a filter with small pores, relying on differences in physical state and component size.

Evaporation

A separation technique used to separate liquids and solutes from a solution by relying on differences in boiling point, such as separating saltwater into sodium chloride crystals and gaseous $H_2O$.

Percentage Composition by Weight

The proportion of a component's mass in a sample, calculated using the formula $\% \text{ weight} = \frac{\text{mass of component in sample (g)}}{\text{total mass of sample (g)}} \times 100$.

Solid

A state of matter characterized by a tightly packed structure that holds its shape and is incompressible.

Liquid

A state of matter with little space between atoms that flows, adapts to the shape of its container, and is incompressible.

Law of Conservation of Mass

The principle stating that the mass of a set of atoms never changes over time regardless of how atoms rearrange, meaning mass of reactants equals mass of products.

Stoichiometry

Calculations based on quantitative ratios of reactants and products in a chemical reaction.

Avogadro's Constant

The number of particles in one mole of a substance, defined as $6.022 \times 10^{23}$.

Molar Mass

The mass of one mole of a substance expressed in $g\,mol^{-1}$, which is equivalent to its atomic or molecular mass.

Limiting Reagent

The reactant short in supply that gets completely used up first in a chemical reaction.

Empirical Formula

The formula representing the simplest whole-number ratio of atoms of each element present in a compound.

Molecular Formula

The chemical formula representing the exact number and type of atoms of each element in a compound.

Solution

A homogeneous mixture containing two or more substances, composed of a solute and a solvent.

Solute

The substance that is being dissolved in a solution.

Solvent

The substance doing the dissolving in a solution, with water being the most common example.

Concentration

The amount of solute per amount of solution, where a higher solute-to-solvent ratio forms a more concentrated solution and a higher solvent-to-solute ratio forms a more dilute solution.

Molarity

The concentration of a solution expressed in moles per litre ($mol/L$), represented by the formula $c = \frac{n}{V}$.

Dilution

The process of decreasing solution concentration by increasing the solvent while keeping the number of solute moles constant ($n_1 = n_2$), using the formula $c_1 V_1 = c_2 V_2$.

Synthesis Reaction

An exothermic reaction involving the combination of multiple reactants to form a single product, such as $2H_2 + O_2 \rightarrow 2H_2O$.

Decomposition Reaction

An endothermic reaction requiring energy in which a single compound decomposes into two or more elements or compounds.

Combustion Reaction

A chemical reaction in which a hydrocarbon reacts with oxygen to form carbon dioxide ($CO_2$) and water ($H_2O$).

Precipitate Reaction

A reaction involving the formation of an insoluble solid precipitate from two aqueous solutions.

Neutralisation Reaction

An acid-base reaction where an acid reacts with a base to form a salt and water.

Acid-Carbonate Reaction

A chemical reaction where an acid reacts with a carbonate to produce a salt, carbon dioxide ($CO_2$), and water ($H_2O$).

Indicators of Chemical Change

Observable signs resulting from chemical bonds breaking and forming, including changes in colour, temperature, precipitate formation, odour, and bubble generation.