==> NaHCO3(aq.) + NaCl(aq.) We will standardize the HCl solution to use it in the titration. The standardization will come as a result of the 1:1 molar ratio above. Thus, the molarity of the HCl solution can be calculated by dividing the number of moles of HCl by the volume of HCl (in liters) used to neutralize the Na2CO3 .
Objectives: The purpose of this lab is to observe the reaction of crystal violet and sodium hydroxide by looking at the relationship between concentration and time elapsed of the crystal violet. CV+ + OH- CVOH To quantitatively observe this reaction of crystal violet, the rate law is used. The rate law tells us that the rate is equal to a rate constant (k) multiplied by the concentration of crystal violet to the power of its reaction order ([CV+]p) and the concentration of hydroxide to the power of its reaction order ([OH-]q). Rate = k[CV+]p[OH-]q To fully understand the rate law, concentrations of the substances must be looked at first. The concentration is measured in molarity.
How do you go from calculated/measured values to accomplishing stated purpose? (4 pts) The purpose of this lab is to determine the exact concentration of an unknown acetic acid solution. Titrations for two different reactions will be performed. Controlled volumes of one reagent are added to a flask containing the other reagent until the equivalence point of the reaction is reached, one between sodium hydroxide (NaOH) and potassium hydrogen phthalate (KHP) and the other between NaOH and acetic acid (CH3COOH). NaOH (aq) + KHP (aq) —› Na+ (aq) + K + (aq) + P2- (aq) + H2O (l) NaOH (aq) + CH3COOH (aq) —› Na+ (aq) + CH3COO- (aq) + H2O (l) The titration of NaOH with KHP will identify the concentration of the NaOH provided.
Double displacement reaction: Chemical reactions in which one component each of both the reacting molecules is exchanged to form the products. 3. What does the stoichiometry of a chemical reaction mean? Why is it important? Stoichiometry is a section of chemistry that involves using the relationships between reactants or products in a chemical reaction to determine the desired quantitive data.
Determine the percent yield of this reaction, showing all steps of your calculation. (3 points) heoretical yield of H2 gas: (1.156 x 10^-3 moles)(1 mole H2/ 1 mole Mg) = 1.156 x 10^-3 moles Theoretical mass: (1.156 x 10^-3 moles)(2.02 g/mole) = 2.335 x 10^-3 g Using ideal gas law: P = (1.1 atm)(760 torr / 1 atm) - 19.8 torr = 816.2 torr V = 0.026 L T = 295 K Solve for n: n = PV/(RT) n = (816.2 torr)(0.026
1) Jeffrey Cox CHE111-DL01 Lab number 10 Stoichiometry of a Precipitation Reaction 2) Purpose/ Intro. In this lab we will be able to calculate the actual, theoretical, and percent yield of the product from a precipitation reaction. We will thusly learn the concepts of solubility and the formation of a precipitate. A precipitate reaction is a reaction in which soluble ions in separate solutions are mixed together to form an insoluble compound that settles out of the combined solution as a solid. The solid then is the insoluble compound, called a precipitate.
Write a hypothesis on what you think will happen when mixed. 3. Combine the substances; record observations. Hydrochloric Acid and Magnesium 1. Add hydrochloric acid to a test tube.
Molarities of solutions and molar concentrations of ions. Dilution. Determination of molar concentration of solutions via acid-base
When an electrolyte or non electrolyte is introduced the effectiveness of the Boiling point changes. III. Data Table A. Boiling points of the solution Solution- NaCl + H2O Temperature measured for 30 Seconds Trial 1 101.3 ̊ C Trial 2 101.7 ̊C Trial 3 102.5 ̊̊C Average of trials 101.8 ̊C IV. Computations A. Calculations in Lab Writeup 1.
Record several points of pH and NaOH added (especially near equivalence point) to be use later to prepare a titration curve. Observations and Results Part I: Solution | pH | 0.1 M HCl | .70 | 0.1 M NaOH | 13.30 | Part II: Volume of 0.1 M NaOH at equivalence point: 35mL pH at equivalence point: 11.45 Molarity of the Unknown Acid A (HCl): 2.0 x 10-4 Discussion In this lab, we found out that water self ionizes itself into hydrogen ion and hydroxide ion naturally to a very small extent. An indicator, in an acid base reaction, is a substance whose color changes over a particular pH range. Phenolphthalein is an example of an indicator which changes from colorless to pink as pH goes from 8 to 10. We plotted the pH against the amount of base added producing a