Chapter 4 Flashcards
What is an acid?
A substance that produces H3O+ when dissolved in water
Acids are characterized by their ability to donate protons (H+) in aqueous solutions.
What is an acid-base reaction?
A reaction involving the transfer of a hydrogen ion between reactant species
This type of reaction is fundamental in acid-base chemistry.
What is actual yield?
The amount of product formed in a reaction
It is often expressed in grams or moles.
Define analyte.
Chemical species of interest
Analytes are typically the substances being measured or analyzed in a chemical reaction.
What is a balanced equation?
Chemical equation with equal numbers of atoms for each element in the reactant and product
Balancing equations is crucial for obeying the law of conservation of mass.
What is a base?
A substance that produces OH− when dissolved in water
Bases are known for their ability to accept protons (H+).
What is a buret?
A device used for the precise delivery of variable liquid volumes, such as in a titration analysis
Burets allow for accurate measurements in quantitative chemical analysis.
Define a chemical equation.
Symbolic representation of a chemical reaction
Chemical equations depict reactants and products using their chemical formulas.
What is a coefficient in a chemical equation?
A number placed in front of symbols or formulas in a chemical equation to indicate their relative amount
Coefficients are essential for balancing chemical reactions.
What is combustion analysis?
Gravimetric technique used to determine the elemental composition of a compound via the collection and weighing of its gaseous combustion products
This method is commonly used for organic compounds.
Define a combustion reaction.
Vigorous redox reaction producing significant amounts of energy in the form of heat and, sometimes, light
Combustion reactions typically involve oxygen as a reactant.
What is a complete ionic equation?
Chemical equation in which all dissolved ionic reactants and products, including spectator ions, are explicitly represented by formulas for their dissociated ions
This representation helps in understanding the reaction mechanism.
What is an endpoint in titration?
Measured volume of titrant solution that yields the change in sample solution appearance or other property expected for stoichiometric equivalence
The endpoint is often indicated by a color change due to an indicator.
What is the equivalence point in titration?
The volume of titrant solution required to react completely with the analyte in a titration analysis
It provides a stoichiometric amount of titrant for the sample’s analyte according to the titration reaction.
Define excess reactant.
Reactant present in an amount greater than required by the reaction stoichiometry
Excess reactants are not fully consumed in the reaction.
What is gravimetric analysis?
Quantitative chemical analysis method involving the separation of an analyte from a sample by a physical or chemical process and subsequent mass measurements
This method provides precise quantitative results.
What is a half-reaction?
An equation that shows whether each reactant loses or gains electrons in a reaction
Half-reactions are useful for balancing redox reactions.
Define an indicator in acid-base reactions.
A substance added to the sample in a reaction titration analysis to permit visual detection of the end point
Indicators help identify the endpoint of titrations by changing color.
What is the definition of insoluble?
Of relatively low solubility; dissolving only to a slight extent
Insoluble substances do not readily dissolve in a solvent.
What is a limiting reactant?
Reactant present in an amount lower than required by the reaction stoichiometry, thus limiting the amount of product generated
The limiting reactant determines the maximum amount of product that can be formed in a reaction.
What is a molecular equation?
Chemical equation in which all reactants and products are represented as neutral substances
It provides a simplified view of the reactants and products without focusing on the ionic nature.
What is a net ionic equation?
Chemical equation in which only those dissolved ionic reactants and products that undergo a chemical or physical change are represented (excludes spectator ions)
This equation highlights the actual chemical change occurring in a reaction.
What is a neutralization reaction?
Reaction between an acid and a base to produce salt and water
This type of reaction is important in titration and pH balancing.
What is oxidation?
Process in which an element’s oxidation number is increased by the loss of electrons
Oxidation is a key part of redox reactions.
What is an oxidation number?
(Also, oxidation state) The charge each atom of an element would have in a compound if the compound were ionic
It helps in determining how electrons are distributed in a compound.
What is an oxidation-reduction reaction?
(Also, redox reaction) Reaction involving a change in oxidation number for one or more reactant elements
These reactions are fundamental in energy production and metabolism.
What is an oxidizing agent?
(Also, oxidant) Substance that brings about the oxidation of another substance, and in the process becomes reduced
Common examples include oxygen, hydrogen peroxide, and halogens.
What is percent yield?
A measure of the efficiency of a reaction, expressed as a percentage of the theoretical yield
Percent yield = (actual yield / theoretical yield) × 100.
What is a precipitate?
An insoluble product that forms from the reaction of soluble reactants
Precipitates can often be seen as solid particles in a solution.
What is a precipitation reaction?
A reaction that produces one or more insoluble products, when reactants are ionic compounds, sometimes called double displacement or metathesis
These reactions are commonly used in analytical chemistry.
What is a product in a chemical reaction?
A substance formed by a chemical or physical change; shown on the right side of the arrow in a chemical equation
Products are the end result of a chemical reaction.
What is quantitative analysis?
The determination of the amount or concentration of a substance in a sample
This analysis is crucial in various fields, including pharmaceuticals and environmental studies.
What is a reactant substance?
Undergoing a chemical or physical change; shown on the left side of the arrow in a chemical equation
Reactants are the starting materials in a chemical reaction.
What is a reducing agent?
(Also, reductant) Substance that brings about the reduction of another substance, and in the process becomes oxidized
Common examples include hydrogen, carbon monoxide, and metals like zinc.
What is reduction?
A process in which an element’s oxidation number is decreased by the gain of electrons
Reduction is the opposite of oxidation in redox reactions.
What is a salt?
An ionic compound that can be formed by the reaction of an acid with a base that contains a cation and an anion other than hydroxide or oxide
Salts are commonly used in food preservation and flavoring.
What is a single-displacement reaction?
A redox reaction involving the oxidation of an elemental substance by an ionic species.
Define solubility.
The extent to which a substance may be dissolved in water, or any solvent.
What does soluble mean?
Of relatively high solubility; dissolving to a relatively large extent.
What is a spectator ion?
An ion that does not undergo a chemical or physical change during a reaction but is required to maintain charge neutrality.
What is a stoichiometric factor?
The ratio of coefficients in a balanced chemical equation, used in computations relating amounts of reactants and products.
Define stoichiometry.
Relationships between the amounts of reactants and products of a chemical reaction.
What is a strong acid?
An acid that reacts completely when dissolved in water to yield hydronium ions.
What is a strong base?
A base that reacts completely when dissolved in water to yield hydroxide ions.
What is theoretical yield?
The amount of product that may be produced from a given amount of reactant(s) according to the reaction stoichiometry.
What is a titrant?
A solution containing a known concentration of substance that will react with the analyte in a titration analysis.
Define titration.
A quantitative chemical analysis method that involves measuring the volume of a reactant solution required to completely react with the analyte in a sample.
What is a weak acid?
An acid that reacts only to a slight extent when dissolved in water to yield hydronium ions.
What is a weak base?
A base that reacts only to a slight extent when dissolved in water to yield hydroxide ions
