Chapter 16 Vocab.

Weak acid

a weak acid only partially dissociates. Examples in water include carbonic acid (H2CO3) and acetic acid (CH3COOH). At equilibrium, both the acid and the conjugate base are present in solution.

Acids

acids are compounds that break up in water to give off hydronium (H+) ions.

indicators

any substance that gives a visible sign, usually by a colour change, of the presence or absence of a threshold concentration of a chemical species, such as an acid or an alkali in a solution. An example is the substance called methyl yellow, which imparts a yellow colour to an alkaline solution.

Amphoteric substance

are substances that display both acidic and basic properties, so they can act as either acids or bases. If an amphoteric substance reacts with a base, then it will take on the role of an acid by being an electron acceptor or proton donor.

Carboxyl group

are weak acids, dissociating partially to release hydrogen ions.

Conjugate acid

within the Brønsted-Lowry acid-base theory, is a species formed by the reception of a proton (H+) by a base—in other words, it is a base with a hydrogen ion added to it.

Buffered Solution

A buffer solution is an aqueous solution consisting of a mixture of a weak acid and its conjugate base

pH meter

A pH Meter is a scientific instrument that measures the hydrogen-ion concentration (or pH) in a solution, indicating its acidity or alkalinity

indicator paper

A roll of universal indicator paper. Colours of universal indicator. A universal indicator is a pH indicator composed of a solution of several compounds that exhibits several smooth colour changes over a pH value range from 1 to 14 to indicate the acidity or alkalinity of solutions.

Titration

A titration is a technique where a solution of known concentration is used to determine the concentration of an unknown solution. Typically, the titrant (the know solution) is added from a buret to a known quantity of the analyte (the unknown solution) until the reaction is complete.

Bronsted-Lowry model

An acid is a proton (hydrogen ion) donor. A base is a proton (hydrogen ion) acceptor. The Bronsted-Lowry theory doesn't go against the Arrhenius theory in any way - it just adds to it. Hydroxide ions are still bases because they accept hydrogen ions from acids and form water

Bases

Arrhenius bases are defined as compounds that cause the formation of the hydroxide ion when placed in water.

Titration curve

Both equivalence points are visible. Titrations are often recorded on graphs called titration curves, which generally contain the volume of the titrant as the independent variable and the pH of the solution as the dependent variable (because it changes depending on the composition of the two solutions).

Conjugate acid-conjugate base pair

In an acid-base neutralization, an acid and a base react to form water and salt. In order for the reaction to carry out

Arrhenius concept of acids and bases

The Arrhenius acid-base concept classifies a substance as an acid if it produces hydrogen ions H(+) or hydronium ions in water. A substance is classified as a base if it produces hydroxide ions OH(-) in water.

Ion-product constant

The Ionic Product of Water, Kw, is the equilibrium constant for the reaction in which water undergoes an acid-base reaction with itself. That is, water is behaving simultaneously as both an acid and a base.

Stoichiometric Point

The equivalence point, or stoichiometric point, of a chemical reaction is the point at which chemically equivalent quantities of acid and base have been mixed. In other words, the moles of acid are equivalent to the moles of base. It can be found by means of an indicator, most often phenolphthalein.

pH scale

The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic

Ionization of water

The self-ionization of water (also autoionization of water, and autodissociation of water) is an ionization reaction in pure water or an aqueous solution, in which a water molecule, H2O, deprotonates (loses the nucleus of one of its hydrogen atoms) to become a hydroxide ion, OH−.

Diprotic acid

diprotic acid is a class of Arrhenius acids which are capable of donating two protons or hydrogen cations per molecule when dissociating in aqueous solutions.

Hydronium ion

hydronium is the common name for the aqueous cation H 3O+ , the type of oxonium ion produced by protonation of water.

neutralization reaction

is a chemical reaction in which an acid and a base react quantitatively with each other. In a reaction in water, neutralization results in there being no excess of hydrogen or hydroxide ions present in solution.

Buret

is a device used in analytical chemistry for the dispensing of variable, measured amounts of a chemical solution. A volumetric burette delivers measured volumes of liquid. Piston burettes are similar to syringes, but with precision bore and plunger.

Standard solution

is a solution containing a precisely known concentration of an element or a substance. A known weight of solute is dissolved to make a specific volume.

Strong acid

one that completely ionizes (dissociates) in a solution (provided there is sufficient solvent). In water, one mole of a strong acid HA dissolves yielding one mole of H+ (as hydronium ion H3O+) and one mole of the conjugate base, A−. Essentially, none of the non-ionized acid HA remains....

Organic acids

organic acid is an organic compound with acidic properties. The most common organic acids are the carboxylic acids

Oxyacids

oxyacid is an acid that contains an oxygen atom bonded to a hydrogen atom and at least one other element.

Completely ionized

this happens in case of a strong acidIt means that all of the ions in an ionic salt are fully disociated into water .it just means that the salt has.