QuestionQuestion

Question:

Write an essay about the main stream molecular descriptors molecular weight (MW), octanol – water partition P (Log P), hydrogen bond donors (HD), hydrogen bond acceptors (HA), rotatable bonds (RT) and polar surface area (PSA) in the context of drug discovery. See for example: Zhu et al. Mol. Inf., 2012, 31, 847-855.

Minimum: 5 pages

Solution PreviewSolution Preview

This material may consist of step-by-step explanations on how to solve a problem or examples of proper writing, including the use of citations, references, bibliographies, and formatting. This material is made available for the sole purpose of studying and learning - misuse is strictly forbidden.

LAB REPORT

June 13th 2017
EXPERIMENT 2 – ACID-BASE TITRATIONS, CHEM 240
Titrimetric analysis of polyprotic acids

AIM: The aim of this experiment was to study acid-base titrations using the potentiometric end point detection. First we standardized the sodium hydroxide solution necessary for titrations and determined the content of citrate in a sample of Enerlyte powder for rehydration.

PROCEDURE: The experiment is done by following the procedure given for the EXP. 2: Acid-Base Titrations, CHEM 240.

Enerlyte:
Expire: 11/16
Batch number: LoTF03L81
Label claim sodium acid citrate 0.53g
Mass Sachet = 5.1268 ± 0.0001 g

Citric acid mass = 0.60739 ± 0.0001 g
Disodium citrate mass = 2.5850 ± 0.0001 g
c(HCl) = 0.1015 mol/L

Errors:
5mL pipette ± 0.01
10mL pipette ± 0.04

RESULTS:
All titrations were performed using autotitrator Metrohm 785 Titrino system. The change of pH is detected by the Metrohm combined glass electrode.

I Strong Acid (HCl) Titration / Standardisation of NaOH titrant
The solution of NaOH is standardized using the standard solution of HCl.( c(HCl) = 0.1015 mol/L). The aliquot of 5.00 mL of HCl standard solution was transferred using a pipette into a titration vessel, diluted with approximately 65 mL of deionized water and titrated using the NaOH solution of unknown concentration.
Table 1: Titration of HCl with NaOH
# pHI pH=7 fixed mL EP mL EP pH
1 2.25 4.897 4.901 7.36
2 2.23 4.927 4.930 7.27
3 2.17 4.942 4.944 7.07
4 2.20 4.937 4.941 7.24
5 2.18 4.931 4.932 7.06


II Titration of citric acid and disodium hydrogen citrate solutions
Citric acid is accurately weighted (about 0.6 g) and dissolved...
$38.00 for this solution

PayPal, G Pay, ApplePay, Amazon Pay, and all major credit cards accepted.

Find A Tutor

View available Analytical Chemistry Tutors

Get College Homework Help.

Are you sure you don't want to upload any files?

Fast tutor response requires as much info as possible.

Decision:
Upload a file
Continue without uploading

SUBMIT YOUR HOMEWORK
We couldn't find that subject.
Please select the best match from the list below.

We'll send you an email right away. If it's not in your inbox, check your spam folder.

  • 1
  • 2
  • 3
Live Chats