Quantitative Chemistry Flashcards

Flashcards for Quantitative Chemistry review.

Chemistry

The science that deals with the composition, structure, and reactions of matter.

Matter

Occupies space and has mass and can be subdivided into mixtures and pure substances.

Mixture

Consists of a number of different substances, not chemically combined together, with a non-constant ratio of components.

Pure substance

Cannot be separated by physical means because its physical properties are constant throughout all samples.

Element

Cannot be split up into simpler substances by chemical means and contains only one type of atom.

Compound

Can be changed into more basic components by chemical means and are made up of different types of atoms chemically bonded together in fixed proportions.

Atom

The smallest particle present in an element which can take part in a chemical change and cannot be split by ordinary chemical means.

Molecule

A small group of atoms joined together by covalent bonds; can be of the same kind (element) or different (compound).

Diatomic

Composed of molecules containing two atoms (e.g., hydrogen gas (H2), nitrogen gas (N2), oxygen gas (O2)).

Monatomic

Exist as single atoms (e.g., noble gases like He, Ne, Ar).

Mole

The amount of a substance containing 6.02 × 10^23 particles of the substance.

Avogadro's Constant

The number of particles in a mole, equal to 6.02 × 10^23 mol–1.

Relative Atomic Mass (Ar)

The ratio of the average mass per atom of an element to 1/12 of the mass of an atom of the C-12 isotope; it has no units.

Relative Molecular Mass (Mr)

The ratio of the average mass of a molecule of the substance to 1/12 of the mass of an atom of the C-12 isotope; it also has no units.

Molar Mass (M)

The mass of one mole of any substance (atoms, molecules, ions, etc.) with the carbon-12 isotope assigned a value of exactly 12 g mol−1.

Empirical Formula

The simplest whole number ratio of elements present in a compound.

Molecular Formula

Indicates the elements present in the compound and the actual number of atoms of these elements in one molecule.

Chemical Equation

A record of what happens in a chemical reaction, showing the formulas of reactants and products and the number of each species required for complete reaction.

Stoichiometry

The study of quantitative (numerical) aspects of chemical equations.

State Symbols

Represent the physical state of substances: (s) - solid, (l) - liquid, (g) - gas, (aq) - aqueous solution.

Limiting Reagent

The reagent that is completely consumed in a reaction and determines the quantity of product formed.

Avogadro's Hypothesis

Equal volumes of gases at the same temperature and pressure contain the same number of particles.

Molar Volume

The volume occupied by one mole of any gas at standard temperature and pressure (STP), which is 22.4 dm^3.

Ideal Gas

A gas in which the particles have negligible volume, there are no attractive forces between the particles, and the kinetic energy of the particles is directly proportional to the absolute temperature.

Ideal Gas Equation

PV = nRT, where P is pressure, V is volume, n is the amount of substance, R is the ideal gas constant, and T is temperature.

Solution

A homogenous mixture of two or more substances where one substance (solute) is dispersed into another (solvent).

Solute

The substance dissolved in a solvent in a solution.

Solvent

The liquid in which a solute is dissolved to form a solution; present in excess.

Concentration

The amount of solute contained within a given volume of solution, typically measured in mol dm-3 or g dm-3.

Titration

A technique involving measuring the volume of one solution that just reacts completely with another solution.

Standard Solution

A solution with an accurately known concentration.

Primary Standard

A substance available in very pure form that is used to prepare a solution of accurately known concentration.