Download Biological chemistry mixing solution and observing and writing data about it and more Lab Reports Chemistry in PDF only on Docsity! Experiment 1: ACIDS, BASES, AND BUFFERS Score: B A L A D A D T A S H I N A A L E X A N . Last name Given name MI BSA 2-7 Course/Year Date performed Date submitted Wednesday 7:00-10:00 Laboratory class schedule Laboratory Instructor/Professor PRE-LAB ACTIVITY UNDERSTANDING CONCEPTS 1. What are the theoretical definition of acids and bases as described by the following? [6pts] 1.1 Arrhenius definition According to Arrhenius, bases are hydroxide compounds that give OH ions when they dissociate in water, while acids are compounds that contain hydrogen and give H+ ions or protons when they do the same in water. 1.2 Bronsted-Lowry definition According to the Bronsted-Lowry definition of acids and bases, an acid is a proton (H+) donor and a base is a proton acceptor. Conjugate bases are produced when Bronsted-Lowry acids lose a proton. Similar to this, a conjugate acid is created when a Bronsted-Lowry base gains a proton. 1.3 Lewis Definition Electron pair transfers are used to define Lewis acids and bases. Lewis bases donate electron pairs, while Lewis acids accept electron pairs. 2. Illustrate using an equation, the meaning of the terms: conjugate acid and conjugate base. Give an example. 3. What is the difference between strong and weak acid? between strong and weak base? What is the ionization constant? What does ionization constant measures? [4 pts] Strong acids are defined as any acid that completely dissociates into ions. It is a weak acid if dissociation is less than 100%. Bases present a similar problem: a strong base is one that is completely ionized in solution. A weak base is one that is less than 100% ionized in solution. The ionization constant, also called acid or base ionization constant, is a mathematical constant used in chemistry to measure the acidity or basicity of a solution. 4. Define and give the formula in determining the pH, pOH, pKa, pKb? How is pH and pOH related? [5 pts] pH is a measure of the concentration of hydrogen ions, [H+], in an aqueous (water) solution. The pH scale has a range of 0 to 14. A low pH value indicates acidity, a pH of 7 indicates neutrality, and a pH of 7 indicates alkalinity. The pOH is the logarithm of OH-ions in solution. pKa is the negative logarithm of Ka. Ka is a solution’s acid dissociation constant. It is a quantitative measure of the acid strength in a solution. The pKb criterion is used to calculate the molecule’s alkalinity. It is used to assess fundamental strength. The formulas to calculate pH, pOH, pKa, Pkb are:
