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Starch is a high molecular mass carbohydrate - (C6H10O5)n. Because of this starch is usually made up as a percentage solution rather as a molar strength.

Depending upon its final use and time available, there are variations on how to make up starch solution. Normally it should be made up fresh, shortly before you need to use it. Distilled or deionised water should be used in all instances described here.

In general, starch is insoluble in water, but some types of starch eg., soluble starch or corn starch will dissolve in water provided they are made into a paste first with cold water then dissolved in boiling water.

There is no hazard normally associated with cold Starch solution other than it may stiffen your lab coat! 
Method 1
This could be used when making up % solution for enzyme practicals.

  • Meausre out 10g of starch powder into a clean 250beaker.
  • Pour in 20-30cm3 of distilled water and mix into a slurry.
  • In a second 1 Litre beaker boil about 500cm3 of water.
  • Add the starch mixture into the boiling water and continue boiling for a few minutes. An electric stirrer or hotplate stirrer could be used here!
  • Make up to the final volume accurately with very cold water
  • Allow to cool

When the starch is completely dissolved in the water, the cloudiness of the solution will dissapear.

Method 2
This is a quick method of making starch solution when final stregnth is not an issue, for example simple test for starch using Iodine solution.

  • Measure out 10g of strach powder into a clean 1 Litre beaker.
  • Boil water in an electric kettle
  • Add hot water to starch powder with continuos stirring for a minute.
  • Allow to cool
Starch solutions will hydrolyse over a period of time and particularly in an acid environment. Therefore if you need to 
store starch solution for a while then it can be preserved with Salicylic Acid.

Labexpert UK in collaboration with Philip Harris and Lady Margaret School for girls, Parsons Green, London SW6 4UN are running a FREE training workshop on the use of the Labexpert Chemical & Equipment Stock Control Software on Tuesday the 13th November 2018, pm.

The course is ideal for staff using the Labexpert UK Chemical and Equipment Stock Control Software or for those who would like to learn more about stock control systems. This will be a hands-on training session and will also include the use of barcode scanners and label printers.

To reserve a place please email This email address is being protected from spambots. You need JavaScript enabled to view it. with full contact details.

A shift in focus by Ofsted away from pupil outcomes will help tackle excessive workload in schools, Amanda Spielman said today. The chief inspector of schools has outlined changes to the way Ofsted will inspect schools from next year, including a move away from focusing on exam results, and new headline judgment areas.

Spielman has also pledged to allow inspectors to spend more time on school sites during inspections, “having those professional conversations with leaders and teachers”.

It will move inspection more towards being a conversation about what actually happens in schools

Its world mental health day. We all have Mental health and it is just as important as your Physical health. Did you know that only 1 in 4 young people actually get the support they need?

So remember to be kind to yourself and others. 2 billion people in this pressure filled world of ours suffer from mental health, yet they don’t feel they can share their feelings/ experiences or how to Fight against the stigma.

If you have dealt with mental health issues yourself, what advice would you give to others, who are suffering in silence?

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UPDATE: 

Microsoft has paused the October update of its Windows 10 operating system after reports that some users found their documents disappeared once it was installed.

On its support page, the firm asks affected customers to use their device as little as possible and to phone their local helpline.

It is also asking people who have downloaded the update manually not to install it.

 

The next version of Windows 10 has arrived and is ready to download as a free update complete with new security enhancements, a load of new emoji (157, I am told), something called a Cloud clipboard, a better search facility, better links to your phone and a smarter SwiftKey-powered keyboard.

Microsoft also promise faster and more considerate updates. If you use your computer in a real live situation (e.g., I use it, live on a radio station each day and on stage as a DJ), it will not forcibly update during these critical times.

When can I get it?

Right now, if you manually check for updates through Windows Update. Otherwise it’ll be pushed out to users over the next month or so. The update will take about 2-3 hours of your life. So its best to do this overnight or have a good magazine and a cup of tea ready.

Can I stop the update?

You can delay the update for a certain period, but you won’t be able to stop it indefinitely. Microsoft only supports older versions of Windows for two years or less from release, so the only way to keep using a supported version of Windows is to keep updating, which is crucial for security.

Labour is set to announce sweeping reforms to England’s school system at its annual conference on Monday.

In a speech, Angela Rayner will announce plans to curtail the freedoms of academy trusts and put councils in charge of opening new schools and deciding who can go to existing ones.

However, one of the Policies has caught my attention. Those among us who remember the Schools Support Staff Negotiating Body maybe interested in this;

Following on from Labour’s manifesto commitment last year to reintroduce the Schools Support Staff Negotiating Body and a national pay settlement for teachers, Rayner will set out plans tomorrow to implement “national pay rules” across all schools.

The SSSNB was set up by the last Labour Government in 2009 to design consistent support staff roles and pay structures in all schools in place of the shambolic and inefficient 'leave it to each school' approach that had existed before and cost the taxpayer hundreds of millions of pounds in equal pay settlements.

Only a year later the coalition government closed the SSSNB down as part of the “bonfire of the quangos” by the then Conservative Education Secretary Michael Gove. This was a callous move that consigned our workforce to exploitation and low pay.

Science Technician – Chemistry or Biology Start date: 5 November 2018 Band 6, full time, term time only

We are seeking to appoint an innovative and enthusiastic individual who has the passion and ability to support high standards of teaching and learning across the subject.

Further information can be found in the Applicant Information Booklet.

Please note that only applications submitted in the School’s application form will be considered. Please download the application form here.

Please submit your completed application form by email to This email address is being protected from spambots. You need JavaScript enabled to view it..

The closing date for receipt of applications is 12:00 noon on Monday, 8 October 2018.

 

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