AboutGeorge Maxwell Expertise I enjoy the challenge of answering any type of question, but please don't post homework questions just "blank"; include something to show you've had a go :-)
Experience I'm a lecturer in chemistry and chemical education in York, UK, and I also act as a Hazchem adviser to the Fire Service, providing chemical safety information to first responders. My professional role also includes providing emergency poisons advice to UK medical practitioners.
Publications Journal of Chemical Education
TES
Plus independent book publications.
Education/Credentials BSc Chemistry (University of York 2005)
PhD Chemistry (NYU)
PGCE Teaching Certification
Past/Present Clients I have previously volunteered in this category, but owing to an email problem, I am re-regestering. I have taught for both Nottinghamshire and Yorkshire education authorities and for several independent youth organisations. I provide continuing support for North Yorkshire Fire and Rescue Service and the UK Poisons Information Service (London-Based).
Question Recently, I had received a stock solution of 15% Glucose/1% Starch from a chemical company. The directions on the bottle instructed the user to measure out a specific small quantity, dilute with 200 ml distilled water, stir to dissolve, then QS to 250 ml. What does QS stand for? I believe it means to dilute to a standard volume of 250 ml. I cannot find the abbreviation anywhere.
Answer Hi There,and thanks for your question.
You are correct in your assumption, the abbreviation QS means "Quantity Sufficient", and translates as "make up to.....ml", using as much solvent as is needed.
Not surprised it threw you, it's an obscure and frankly silly bit of redundant nomenclature, nowadays replaced with the phrase "make up to .....ml". You were unlucky that the company you're dealing with isn't up-to-date in its labelling!
