Showing posts with label back titration. Show all posts
Showing posts with label back titration. Show all posts

Friday, March 25, 2022

Chinese Milk Scandal

 When we buy food from a shop, we assume that food is safe to eat, but sometimes it isn't!

In 2008 six babies died from kidney stones and an estimated 54,000 babies were hospitalized in China after being fed "Infant Formula" (baby milk) adulterated with melamine, an industrial chemical. It is thought that about 300,000 babies in total were affected by what came to be known as the "Chinese Milk Scandal".

Why was melamine added to Infant Formula? And why did it take so long to discover its addition?

Read more in this edition of AUS-e-NEWS:

Subscribe to AUS-e-NEWS at https://www.ausetute.com.au/ausenews.html

 

Friday, July 17, 2015

HCl as a Primary Standard?

Question: Why is HCl not suitable as a primary standard?
Answer:  There are three main reasons why HCl is not suitable as a primary standard:
  • HCl is not a solid at room temperature and pressure. 
  • HCl cannot be obtained at a very high purity.
  • HCl does not have a high molecular mass.
You can find out more about what makes, and does not make, a primary standard at:
http://www.ausetute.com.au/titrstand.html

Sunday, June 21, 2015

What is the best indicator for titration?

Question: What is the best indicator for titration?
Answer: That all depends on what you are titrating!

If you doing an acid-base titration, then you will need to know the relative strengths of the acid and base you going to be using.
Once you have determined an approximate pH for the equivalence point of the neutralisation reaction, you use this as the pH of the endpoint of the titration in order to determine the best acid-base indicator to use.

Friday, July 18, 2014

Standard Solutions

What is the difference between a primary standard and a secondary standard in volumetric analysis?
What substances can be used as a primary standard?
How do you make a standard solution?

All these questions are answered in AUS-e-TUTE's new tutorial on standard solutions.
Members should log-in and go to the Volumetric Analysis section on the index page, or,
follow the links from your Chemistry syllabus study guide.
Members will also find a game, test and exam as well as tutorial on this topic.
Teachers will find  a worksheet wizard which will let you make, and print off, a worksheet on this topic.

Not an AUS-e-TUTE Member?
There is currently a "free-to-view" tutorial at http://www.ausetute.com.au/titrstand.html


Sunday, March 23, 2014

Ethanol Content of Beer and Wine

AUS-e-TUTE has added new resources for determining the content of ethanol in alcoholic beverages such as beer and wine.
Members should go to :
http://www.ausetute.com.au 
and log-in to the Members Only Test Centre to find the new Ethanol Redox Titration tutorial, game and test.
Teachers will find a new worksheet wizard for preparing Ethanol Redox Titration worksheets in the Teachers Only section of the website.