First and Second Semester Chemistry Final Exam Review Flashcards

Comprehensive vocabulary flashcards covering basic measurement, matter classification, energy calculations, atomic structure, nuclear chemistry, and stoichiometry based on the semester review guide.

Qualitative Observation

A description using the senses without the use of numbers, such as color, smell, or texture.

Quantitative Observation

A description that involves numerical measurements, such as a mass of $10.0\,g$ or a temperature of $30.0\,^{\circ}C$.

Graduated Cylinder

The best piece of equipment used to measure volume, typically measured in milliliters ($cm^3$).

Balance

The best piece of equipment used to measure mass, which is recorded in grams ($g$).

Significant Figures (Sig Figs)

Specific digits in a number that carry meaning contributing to its precision, including all non-zero numbers and certain zeros like 'Right-Right Zeros' after a decimal.

Physical Change

A type of change where a pure substance undergoes a transformation (like a phase change, dissolving, or breaking) without losing its chemical identity.

Chemical Change

A transformation that results in a new substance, indicated by signs such as flammability, gas production, color change, precipitate formation, or light emission.

Precipitate

A solid that forms out of a mixture of two liquids during a chemical reaction.

Element

A pure substance made of only one kind of atom, such as $Li$, $N$, or $He_2$.

Compound

A substance consisting of two or more different kinds of atoms chemically bound together, such as $MgCl_2$ or $H_2O$.

Mixture

A material composed of two or more different substances in the same container that are not chemically bonded.

Catalyst

A substance that speeds up a chemical reaction without being consumed in the process.

Specific Heat

The amount of energy required to raise the temperature of $1.0\,g$ of a substance by $1.0\,^{\circ}C$. Units are given in $J\,g^{-1}\,^{\circ}C^{-1}$ or $cal\,g^{-1}\,^{\circ}C^{-1}$.

Heat of Fusion ($H_f$)

The amount of energy required to melt or freeze $1.0\,g$ of a substance, measured in $J\,g^{-1}$ or $cal\,g^{-1}$.

Atomic Number

The number of protons in an atom, which identifies the identity of the element.

Mass Number

The total number of protons and neutrons in the nucleus of an atom.

Isotopes

Atoms of the same element that have the same number of protons but a different number of neutrons, resulting in a different mass.

Cation

A positively charged ion formed when an atom loses one or more electrons.

Ionization Energy

The energy required to remove one valence electron from an atom; it increases as you move left to right and up on the periodic table.

Alpha Decay

A nuclear reaction where an atom releases an alpha particle ($^4_2He$), decreasing the mass number by $4$ and the atomic number by $2$.

Fission

A nuclear reaction involving the splitting of a large nucleus into smaller nuclei, releasing energy and neutrons.

Fusion

A nuclear process where small nuclei combine to form a larger nucleus and release energy.

Valence Electrons

The electrons in the outermost energy level of an atom that determine its chemical reactivity and bonding behavior.

Solvent

The substance in a solution that does the dissolving, such as water in a sugar water mixture.

Solute

The substance in a solution that is being dissolved, such as sugar in a sugar water mixture.

Exothermic Reaction

A chemical or physical process that releases energy into its surroundings.

Endothermic Reaction

A chemical or physical process that absorbs energy from its surroundings.

Avogadro's Number

The number of particles (atoms, molecules, or formula units) in one mole of a substance, equal to $6.02 \times 10^{23}$.

Limiting Reactant

The substance in a chemical reaction that is completely consumed first, thereby limiting the amount of product formed.

Titration

A laboratory technique used to determine the concentration of a solution by reacting it with a solution of known concentration.

pH

A measure of the acidity or basicity of a solution, calculated as $-\ln[H^+]$, where values below $7$ are acidic and above $7$ are basic.

Gas Pressure

The force exerted by gas particles colliding with objects or the walls of their container.