Calculate the concentration of caffeine

Assignment Help Chemistry
Reference no: EM133151002

SMA0020 Practical Determination of the relative proportions of caffeine and aspirin by GC-MS

The purpose of this experiment is to determine the concentration of caffeine and ethyl-2- acetoxybenzoate (aspirin derivative) contained in the solution provided. A calibration curve will be constructed using standards, then the unknown sample will be measured and its caffeine and ethyl-2-acetoxybenzoate content calculated.

Your graphs (drawn in Excel or a similar program) and your chromatograms must be attached to your report.

Part 1 - Calibration curve
Run each standard solution once, starting with the lowest concentration. Record your measurements in the table below and plot separate calibration graphs for peak area and peak height vs. concentration for each standard (four graphs in total).
Caffeine:

Ethyl-2-acetoxybenzoate:

Part 2 - Analysis of unknown solution
Record the peak areas and peak heights for the unknown sample in triplicate.
Caffeine:

Ethyl-2-acetoxybenzoate:

Calculate the concentration of caffeine and ethyl-2-acetoxybenzoate in the unknown solution, including an error value:

Questions (continue over the page if necessary)
1. Why are calibration standards always analysed in increasing order of concentration?

2. Comment on the linearity of your calibration graphs

3. Comment on the magnitude of the errors in your measurements of the unknown concentration.

Attachment:- Caffeine and aspirin.rar

Reference no: EM133151002

Questions Cloud

Critically Evaluate the Corporate Governance Report : Critically Evaluate the Corporate Governance Report 2020 and explain in your own opinion whether the objectives of MCCG2017 is achieved
How much is the amount of Retained earnings at year-end : 1st Quarter: Declared and issued 20,000 share dividends when the market value per share is P18.50. How much is the amount of Retained earnings at year-end
Calculate the net present value of the case : A total initial investment of L500,000.00, and a minimum acceptable rate of return of 18%. Calculate the net present value of the case (VPN)
Completing the titration and adjust step size : Plot graph overleaf as you are completing the titration and adjust step size as needed - Calculation of precise concentration of HCl from pH titration value
Calculate the concentration of caffeine : Calculate the concentration of caffeine and ethyl-2-acetoxybenzoate in the unknown solution, including an error value
Determine the concentration of caffeine : Determine the concentration of caffeine and ethyl-2- acetoxybenzoate (aspirin derivative) contained in the solution provided
Evaluate suitability and effectiveness of the hedging tools : Evaluate the suitability and the effectiveness of the hedging tools used by the grab company in managing the risks identified by you
Calculate the estimated quantity of beach umbrellas : Calculate the estimated quantity of beach umbrellas that need to be produced in July, August, September, and October
How much should be recorded as revenue : Question - Page Inc. made a $20,000 sale on account with the following terms: 2/15, n/30. How much should be recorded as revenue

Reviews

Write a Review

Chemistry Questions & Answers

  Calculate the ph of a solution

Calculate the pH of a solution containing 25.00 mL of 0.12M formic acid (Ka=1.7x10^-4) to which the following amounts of 0.10M NaOH have been added:

  When a 125-gram sample of limestone was dissolved in acid

when a 1.25-gram sample of limestone was dissolved in acid 0.44gram of co2 was generated. if the rock was dissolved in

  How much heat did this sample absorb

How much heat did this sample absorb?

  Compute the number of atp molecules acquired

Compute the number of ATP molecules acquired from the anaerobic conversion of each of the following sugars to lactate. (a) glucose

  Explain the person to expel the food item from the airway

You put your arm around the persons waist and use your fist to push up on the persons abdomen, an action called the Heimlich maneuver. a) How would this action change the volume of the chest and lungs? b) Why does it cause the person to expel the ..

  Explain how much heat is absorbed by the ice cube

The mass of the ice cube is 14.6 g, and its initial temperature is -13.1 °C. The water resulting from the melted ice reaches the temperature of your skin, 30.7 °C. How much heat is absorbed by the ice cube and resulting water

  What is the partial pressure of hi at equilibrium

Problem- A 35.0-L vessel at 700 K initially contains HI(g) at a pressure of 6.90 atm; at equilibrium, it is found that the partial pressure of H2(g) is 0.668 atm.

  Initial metabolic experiments are generally carried out

Initial metabolic experiments are generally carried out in unfractionated cell-free homogenates. However, localising a metabolic pathway within a specific cell compartment requires fractionating the homogenate to separate the intracellular organelles..

  What is the mass of the solid nh4cl formed

What is the mass of the solid NH4Cl formed when 73.0 g of NH3(g) are mixed with an equal mass of gaseous HCl? What is the volume and identity of the gas remaining, measured at 14.0°C and 752 mmHg? (8 points)

  Write the net ionic equation for the reaction

Write the net ionic equation for the reaction. Calculate the equilibrium constant for the reaction.

  Explain what percentage of the original carbon-14

The half-life of carbon-14 is 5730 years. Therefore, 5730 years after being cut from a tree, a piece of wood will have 50.0 % of the carbon-14 that it had originally. What percentage of the original carbon-14 will remain in the wood after another 5..

  State chemical process is designed to produce ethylene

A chemical process is designed to produce ethylene from ethane according to the reaction: C2H6 (ethane) ? C2H4 (ethylene) + H2 The fresh feed to the process contains pure ethane at a flowrate of 100 mole/min. The fresh feed is mixed with a recycl..

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd