Constant

Experiment 4: Kinetics of Nucleophilic Substitutions 1. Determine the effect of varying [OH-] on the rate of the reaction. To do this, you should complete the following table: Experiment [tBuCl]0 (M) [OH-]0 (M) Time (s) Reaction rate (M/s) Rate constant (s-1) 1 0.03 0.003 65 4.89 · 10-5 1.62 · 10-3 2 0.03 0.006 213 3.15 · 10-5 1.05 · 10-3 3 0.03 0.009 362 2.96 · 10-5 9.85 · 10-4 What is the dependence of [OH-] on the rate law? The effect of the increased or…

The purpose of this lab is to determine the Ka of an indicator within an unknown solution. This can be determined because acid-base indicators are weak bases or acids, and when neutralized they change colors. The color change is measured by the light absorption spectra in the compound which can be used to calculate the concentration. This experiment measures the concentrations by the different pH values which allows the pKa and Ka to be determined. Through the experiment, and the recorded color…

equilibrium of the molecules. During this lab we will separate two compounds from one solute that will be formed by amalgamating a ‘slurry’ – provided by the instructor. Resin or cellulose is used to create a sound support unit in order maintain a constant positive or negative charge respectively, this will allow separation to occur when equilibrium is shifted during the reaction. The column will have a support unit – composed of either cellulose or resin, inserted with varying concentrations of…

To determine optimal pH value for the hydrolysis of p-NPG by leukocyte GCase, we examined effects of variable pH (4.0-5.5) at a constant substrate concentration (5mM). Figure 1 shows the pH activity curves of leukocyte GCase assayed in the presence and absence of 6 mg per ml Sodium taurocholate. In the absence of the pure sodium taurocholate, the activity in the range of pH 4.0-4.8 was considerably lower. However, in the presence of pure Sodium taurocholate, leukocyte GCase was optimally active…

Part A: Background Information Acids and bases are very common in today’s society, and they can be found in most households. Acids can be found as by-products of air pollution, concrete cleaner, food flavouring and is produced by the muscle. Bases are found in most cleaning products as ammonia or sodium hydroxide, and they also treat indigestion. There are many ways that acids and bases can be defined by their chemical properties. The Bronsted-Lowry definition states that acids are proton…

Discussion of Results and Scientific Explanation To achieve the goal of determining an unknown acid or base, anion and cation test were performed. These tests allowed for the components of the solutions to be identified, therefore, achieve the second goal. The pH was also used in to help find the identity of the unknown solutions and it was used to draw conclusions about the solutions. Dilutions were used to help understand the different behaviors of different concentrations. Household items…

how the Henderson-Hasselbalch equation works and to apply and hone the skills of pipetting, buffer-making, pH-meter use and graphing. The primary goal of the practical was to determine the pKa value of a weak acid. The Ka is an acid dissociation constant, it is a quantitative measure of the strength of an acid in solution. The pKa is defined as the negative log of the Ka, pKa= -log Ka. The lower the value for the pKa the more acidic the acid (greater concentration of H+ ions). The pKa of a…

What are buffer solutions? Buffer solutions are solutions in water that mark the mixture of acids and bases. They assist in neutralization response to a certain quantity. Acidic buffer answers are those that have robust acids and weak bases as their components. they're used for neutralizing alkaline solutions. Alkaline or primary buffer answers are those who have sturdy alkalis and weak acids within themixture. they're used for neutralizing acidic aqueous answers. Buffer solutions in the blood…

Plant Science - Seed germination and growth The research question: What is the effect of changing the pH of the soil on the germination and growth of mustard peas? Hypothesis: The greatest number of peas will germinate and will grow the most when the pH is 5 or 7. Theory: Enzymes play a vital role in the cells of plants (especially when growing) and enzymes work best when at their optimum pH value. Moreover, all chemical reactions have an optimum pH at which they work best (Howard and…

Question 1: pH can be described as a measure of acidity or basicity (Alkalinity) of a solution. It is exactly equal in amount to the negative log of the concentration of hydronium(H3O+) ions. Due to the negative log relationship, increased hydronium ions transform to lower pH. When we add it to water, an acid releases hydrogen ion. Hydrogen ions in water unite with the water molecules to form hydronium ions, thereby lowering the pH and increasing the acidity of water. Water exposed to air is…