Chemistry and Chemical Reactions Flashcards

Flashcards covering chemical reaction theory, scientific measurement errors, periodic table trends, and chemical bonding and naming conventions.

Collision Theory

Explains that chemical reactions occur as a result of collisions between reacting particles.

Activation Energy

The minimum energy required for a reaction to occur; it is needed to break bonds within reactants.

Catalysts

Substances that speed up reactions without being consumed by providing a new reaction pathway with a reduced activation energy barrier.

Rate of Reaction

The change in concentration of a reactant or product per unit time.

Instantaneous Rate

The rate of change at a particular moment in time during a chemical reaction.

Average Rate

The rate of change over a specific period of time during a chemical reaction.

Accuracy

The closeness of a measurement to the correct true value; it determines how valid a measurement or experiment is.

Precision

The closeness of several independent measurements of the same quantity to each other; it determines how reliable a measurement or experiment is.

Systematic Errors

Consistent errors in magnitude or direction that primarily affect accuracy and validity, often caused by imperfect instrument calibration or process errors.

Random Errors

Fluctuating errors that vary in magnitude and direction, primarily affecting precision and reliability; they cannot be eliminated but can be minimized.

Error

The difference between the true value of the measured quantity and the measured value, used when making conclusions about accuracy.

Uncertainty

The range of values within which the true value of a measurement is asserted to lie with some level of confidence, used when making conclusions about precision.

Absolute Uncertainty

The size of the range of values in which the true value probably lies; for multiple trials, it is calculated as $\frac{x_{max} - x_{min}}{2}$.

Atomic Number

The number of protons and electrons in a neutral atom, identifying the element's position on the periodic table.

Atomic Mass

The sum of the number of protons and neutrons in an atom's nucleus.

Groups

Vertical columns on the periodic table where elements have the same number of valence electrons and similar physical and chemical properties.

Periods

Horizontal rows on the periodic table where elements have the same number of electron shells.

Ductility

The physical property describing a material's ability to be stretched out into a wire.

Malleability

The physical property describing a material's ability to change shape or be hammered thin without breaking.

Cations

Positively charged ions, typically metals, formed when an atom loses electrons to achieve a full valence shell.

Anions

Negatively charged ions, typically non-metals, formed when an atom gains electrons to achieve stability.

Alkali Metals

Group 1 soft, low-density metals (excluding Hydrogen) that react violently with water to form alkaline solutions.

Alkaline Earth Metals

Group 2 reactive metals that are harder and denser than alkali metals.

Transition Metals

Groups 3–12 hard, dense metals with high melting points that often form colored compounds and are used as catalysts.

Halogens

Group 17 highly reactive non-metals known as 'salt formers' that readily bond with metals.

Noble Gases

Group 18 elements with full valence shells that are unreactive and do not typically form compounds.

Ionic Bonding

Strong electrostatic attraction between metal cations and non-metal anions resulting from the transfer of valence electrons.

Covalent Bonding

Bonding between non-metal atoms through the sharing of electron pairs to acquire a stable noble gas configuration.

Metallic Bonding

Bonding formed by electrostatic forces between metal cations and delocalized electrons that are free to move within the structure.

Univalent Element

An element that has only one possible charge as an ion.

Multivalent Element

An element, like copper, that can form an ion in more than one way, requiring Roman numerals in naming (e.g., Copper II).

Polyatomic Ions

Groups of atoms covalently bonded together that stay together in chemical reactions and have a specific net charge, such as Sulfate ($SO_4^{2-}$).

Diatomic Elements

Pure elements composed of only two atoms bonded together, including $H_2$, $N_2$, $F_2$ , $O_2$, $I_2$, $Cl_2$, and $Br_2$.

Law of Conservation of Mass

States that mass is neither created nor destroyed; the number of atoms in the reactants must equal the number of atoms in the products.

Synthesis Reaction

A chemical reaction where two or more reactants combine to form a single product ($A + B \rightarrow AB$).

Decomposition Reaction

A chemical reaction where one reactant breaks apart into two or more different products ($AB \rightarrow A + B$).

Single Displacement

A reaction where a more active element replaces a less active element in a compound ($A + BC \rightarrow AC + B$).

Combustion

A reaction where a compound reacts with oxygen to release large amounts of heat and light; hydrocarbons form $CO_2$ and $H_2O$.

Neutralisation

A double displacement reaction between an acid and a base that forms a salt and water.

Precipitation Reaction

A reaction where multiple soluble reactants combine to form an insoluble solid product called a precipitate.

Binary Acid

An acid made up of only two elements: hydrogen and one other non-metal, named with the prefix 'hydro-' and suffix '-ic'.

Oxyacid

An acid containing hydrogen and a polyatomic ion that includes oxygen.

Isotopes

Atoms of the same element with the same number of protons but a different number of neutrons.