Acid-Base Titration Using a Ph Meter
Acid-Base Titration Using a pH Meter
Bradley Holloway and Jennifer Parker
Period 6
April 16, 2013
Introduction:
In chemistry, the ability to find molarities of acidic and basic solutions is a convenient way to convert between moles of solute and the volumes of their solutions. Through the process of titration, the molarity of these acids and bases can be found to a high level of precision. To begin titration, one solution is added to a second solution slowly until a certain point where a chemical reaction reaches completion. The titrant (the first solution) is used to titrate the second solution until the reaction is complete. This endpoint is usually marked with an indicator that produces a color. The titrant is a solution with a known molarity in order to determine the molarity of the other. (Clark) Titration is typically done by filling a buret clamped to a ring stand with solution one and slowly transferring it to solution two in a flask underneath the buret. In solution two, a certain amount of some indicator must be dropped into the flask for the endpoint to be visibly reached. This process would be repeated multiple times to eliminate random error. (Svante) In this lab the base NaOH will be used to fill the buret and act as the titrant. Then flasks of acetic acid solution will be placed beneath the buret full of NaOH. Then, the base will slowly be added to the solution until the endpoint is reached and the bright pink color fills the liquid inside the container. Once the reaction has reached completion, the process will be repeated. (Tissue) However in this lab the solution will be monitored with a digital pH meter. A pH meter uses circuitry to determine the concentration of the hydroxide ions in the solution and then converts that to a pH that can be read from a computer. In this lab the pH meter will be hooked up with Vernier’s Logger Pro to collect large amounts of data and easily visualize the titration curve. This
Bradley Holloway and Jennifer Parker
Period 6
April 16, 2013
Introduction:
In chemistry, the ability to find molarities of acidic and basic solutions is a convenient way to convert between moles of solute and the volumes of their solutions. Through the process of titration, the molarity of these acids and bases can be found to a high level of precision. To begin titration, one solution is added to a second solution slowly until a certain point where a chemical reaction reaches completion. The titrant (the first solution) is used to titrate the second solution until the reaction is complete. This endpoint is usually marked with an indicator that produces a color. The titrant is a solution with a known molarity in order to determine the molarity of the other. (Clark) Titration is typically done by filling a buret clamped to a ring stand with solution one and slowly transferring it to solution two in a flask underneath the buret. In solution two, a certain amount of some indicator must be dropped into the flask for the endpoint to be visibly reached. This process would be repeated multiple times to eliminate random error. (Svante) In this lab the base NaOH will be used to fill the buret and act as the titrant. Then flasks of acetic acid solution will be placed beneath the buret full of NaOH. Then, the base will slowly be added to the solution until the endpoint is reached and the bright pink color fills the liquid inside the container. Once the reaction has reached completion, the process will be repeated. (Tissue) However in this lab the solution will be monitored with a digital pH meter. A pH meter uses circuitry to determine the concentration of the hydroxide ions in the solution and then converts that to a pH that can be read from a computer. In this lab the pH meter will be hooked up with Vernier’s Logger Pro to collect large amounts of data and easily visualize the titration curve. This
Cited: Clark, J. (n.d.). acid-base indicators. chemguide: helping you to understand Chemistry - Main Menu. Retrieved October 8, 2012, from http://www.chemguide.co.uk/physical/acidbaseeqia/indicators.html Svante Arrhenius ' Acid Base Theory. (n.d.). D. W. Brooks Site. Retrieved October 8, 2012, from http://dwb4.unl.edu/Chem/CHEM869R/CHEM869RLinks/www.nidlink.com/7Ejfromm/ arrhenius.htm Tissue, Brian. Acid-Base Titrations. (2000) Chemistry Hypermedia Project. Retrieved October 8, 2012 from http://www.files.chem.vt.edu/chem-ed/titration/acid-base-titration.html