Chapter 19 Key Concepts Flashcards
How did Arrhenius define an acid and a base?
Acids are hydrogen-containing compounds that ionize to yield hydrogen ions (H+) in aqueous solution. Bases are compounds that ionize to yield hydroxide ions (OH-) in aqueous solution
What are the properties of acids and bases?
Acids taste sour, will change color of an acid-base indicator, and can be strong or weak electrolytes in aqueous solution. Bases taste bitter, feel slippery, will change the color of an acid-base indicator, and can be strong or weak electrolytes in aqueous solution
How are acids and bases defined by the Brønsted-Lowry theory?
It defines an acid as a hydrogen-ion donor and a base as a hydrogen-ion acceptor
What is the Lewis theory of acids and bases?
An acid accepts a pair of electrons during a reaction, while a base donates a pair of electrons
What is the relationship between [H+] and [OH-] in an aqueous solution?
The product of the hydrogen-ion concentration and the hydroxide-ion concentration equals 1.0X10^-14
What is true about the relative concentrations of hydrogen ions and hydroxide ions in a basic, acidic, and neutral solution?
A solution in which [H+] is greater than 1X10^-7 M has a pH less than 7.0 and is acidic. The pH of pure water or neutral aqueous solution is 7.0. A solution with a pH greater than 7 is basic and has a [H+] of less than 1X10^-7 M.
What is true about the colors of a pH indicator?
It’s acid form and base form have different colors in solution
Compare a strong acid and a weak acid in terms of the acid dissociation constant.
Weak acids have small Ka values. The stronger an acid is, the larger is it’s Ka value
How do you determine the Ka of a weak acid or the Kb of a weak base?
Substitute the measured concentrations of all the substances present at equilibrium into the expression for Ka or Kb
What are the products of a reaction between an acid and a base?
Water and one of a class of compounds called salts
What occurs at the endpoint of a titration?
The point of neutralization
What type of salt produces an acidic solution? A basic solution?
Salts that produce acidic solutions contain positive ions that release protons to water. Salts that produce basic solutions contain negative ions that attract protons from water
What substances are combined to make a buffer?
A weak acid and one of its salts, or a solution of a weak base and one of its salts
