• Re: Optical rotation and specific rotation q.

    Updated: 2010-03-10 23:44:26
    Quote from: coolio_person on Today at 12:22:55 PMwhich would you say is "correct"?Both. Method is not specific enough to differentiate between these two.

  • Re: bit of trouble with this question on isomers of butan-1-ol

    Updated: 2010-03-10 23:24:49
    As a general approach to "generating" isomers within the same homologous group I do the following steps1. Make as many distinct carbon chains as possible. This means start with the straight chain then introduce branches and side chains. Single C-C bonds can take pretty much any angle in a rough structural diagram and still remain the same molecule. Also rotation about a C-C bond will allow side chains and groups to appear to be in new positions in the diagram where they actually represent the same molecule2. Place the non-CH groups such as -OH in as many different positions on the chains created in 1. above as possible. Obviously as the number of groups increase there are more potential permutations of position on the chain created in 1.3. Swap some of the atoms in the groups to create new groups such as converting an -OH to a C=O. Check the molecular formula is still correct and do step 2 again

  • Re: Optical rotation and specific rotation q.

    Updated: 2010-03-10 23:22:55
    That's what I thought, but then i got confused with why we had to calculate the concentration in the first place because they give use the specific rotation as part of the question in part "a" (130 degrees). So I don't see the point of part "a", because it hasn't anything to do with part "b"....AND the answer for part "b" is mentioned in the question of part "a". It's honestly really confusing!The values closest to 130 degrees is melibiose (129.5 degrees) and maltose (130.4 degrees) ...I was taught that we should round up if a decimal was .5 and up, and we should round down if a decimal was .4 or less...so essentially they're both about 130 degrees...which would you say is "correct"?

  • Partnering with Industry to Build a Sustainable Workforce

    Updated: 2010-03-09 19:30:00
    As budgets tighten and resources shrink, partnerships between industry and academe become increasingly critical to the sustainability of the chemistry-based technology workforce. Join the Division of Chemical Education (CHED) and the Committee on Technician Affairs (CTA) for "Partnerships with Industry: Building a Sustainable Workforce." This half-day symposium will explore the role of partnerships in the education and professional development of technicians, operators, analysts, and other applied chemical technology professionals. For more information, contact the ACS Office of Two-Year Colleges.

  • Leadership Training in San Francisco

    Updated: 2010-03-09 19:30:00
    According to a recent survey, the top skills most wanted by employers are leadership, strategic thinking, and communication skills. To help you build these marketable skills, ACS is offering five highly-regarded leadership courses at the upcoming Spring National Meeting: Leading Change: how to lead change and manage resistance; Leading Without Authority: how to gain cooperation; Strategic Planning: how to develop a strategic plan; Coaching & Feedback: how to coach others; and Engaging Colleagues in Dialogue: how to listen and communicate effectively. Contact your Local Section or Division officers about 50% off scholarships, or contact leaders@acs.org. Space is limited - enroll today!

  • Last Chance to Submit Abstracts for Green Chemistry Conference

    Updated: 2010-03-09 19:30:00
    Abstract submissions will be accepted until this Friday, March 12, for the 14th Annual Green Chemistry & Engineering Conference; choose from over 15 different green chemistry and engineering technical sessions. The conference returns this year to downtown Washington, DC, on June 21-23, 2010. Registration and housing reservations are open, too. For more information, visit the conference website, www.gcande.org, or contact us with e-mail at greenchem2010@acs.org or by phone at (202) 872-6102.

  • Inquiry in Action: Free Physical Science Activities Online

    Updated: 2010-03-09 19:30:00
    Go to www.inquiryinaction.org for free inquiry-based physical science activities that support national science content standards. All activities and the companion 470-page book are available for free download. The site also features a chemistry background section complete with molecular model animations and videos, plus information on upcoming workshops based on the book.

  • O Level Chemistry: Mole Calculations – Concentrations of Solutions

    Updated: 2010-03-09 01:33:25
    In Mole Calculations, many students lose marks in questions related to Volumetric Analysis, especially on those that requires them to understand the concepts of CONCENTRATIONS of solutions. Volumetric Analysis are always a highlight in our annual Mole Calculations Mastery Workshop. Concentrations of a solution refers to the amount of solute dissolved in 1 dm3 of the [...]

  • O Level Chemistry: Mole Calculations – Balanced Chemical & Ionic Equations

    Updated: 2010-03-08 05:56:46
    As you can see from the on-going survey on the right hand side, Mole Calculations (commonly known as Mole Concepts) has been voted by students as the #1 Killer Topic in O Level Chemistry (and other equivalent basic Chemistry Syllabus). In fact, a large number of students skip the calculation-based questions when they see it on [...]

  • Extension to Early Bird Price Registration for Mole Calculations Mastery Workshop 2010

    Updated: 2010-03-05 01:00:00
    Quick Announcement for Singapore Readers: Extension to Early Bird Price Registration for Mole Calculations Mastery Workshop 2010 We received a handful of requests for us to extend the bird early registration for the workshop as many schools in Singapore have yet to announce their March Holidays schedule. We hear you and would want to help committed students to [...]

  • Toxin detection, in the palm of your hand

    Updated: 2010-03-04 14:00:00
    Researchers detect and quantitate unlabeled chemical toxins with a portable device.

  • Registration for 2010 GCE ‘N’, ‘O’ & ‘A’ Levels Examinations for Private Candidates

    Updated: 2010-03-04 08:24:51
    Registration for 2010 GCE ‘N’, ‘O’ & ‘A’ Levels Examinations for Private Candidates Dateline: 3 April 2010 For more information, please call MOE Customer Serive at 6872 2220 or visit http://www.seab.gov.sgRelated Articles: 2009 GCE N, O and A Levels Examinations: For Private Candidates 2009 GCE O Level Examination Calendar (Tentative) Official: Release of 2009 GCE ‘O’ Level Results on 11th [...]

  • Chemistry YouTube Videos – February 2010 Roundup

    Updated: 2010-03-03 20:57:36
    A student in a chicken suit gets tackled by organic chemistry lecturer Owen Priest at Northwestern University. An excellent video on methane by the Periodic Table of Videos crew last month. Safety Note: Samantha “Pants!” Tang is not wearing a lab coat, gloves, and her hair is not fully pulled back. Also from the Periodic Table of Videos, [...]

  • O Level Chemistry: Mole Calculation Exam-Based Application Question

    Updated: 2010-02-27 17:09:23
    Mole Calculations, or commonly known as “The MOLE” or “Mole Concepts” is regarded by many of the GCE ‘O’ Level Chemistry students (as well as IGCSE and IB / IP Chemistry students) to be one of the most challenging and difficult topic. Let’s not mention that many students are not able to score in this topic! In [...]

  • Pittcon 2010 In Orlando

    Updated: 2010-02-18 14:00:00
    This year’s pittcon aims to be the most comprehensive conference and exposition on laboratory science.

  • Android Spectroscopy

    Updated: 2010-02-16 02:46:02
    I was jealous when I saw Joel write about his boss using his iPhone’s light source for experiments (finally, a really useful science iphone app). I knew I had to one-up him for no other reason then I am a Google Android user. Below is a video of an app I made; the app will [...]

  • Foil And Tape Serve Raman

    Updated: 2010-02-04 14:00:00
    Pastelike silver dendrites generated on aluminum foil and transferred to Scotch tape serves as a substrate for SERS.

  • Udo A. Th. Brinkman wins ACS Award in Chromatography

    Updated: 2010-02-04 14:00:00
    ACS Award In Chromatography.

  • Naked-eye colorimetric analysis of heparin and its derivatives

    Updated: 2010-01-28 14:00:00
    A new colorimetric technique could provide a rapid, naked-eye assay of heparin levels in serum.

  • Raman microscopy maps of drug-delivery vehicles

    Updated: 2010-01-14 14:00:00
    A Raman mapping technique provides spatial information on the chemical makeup of microspheres.

Previous Months Items

Feb 2010 | Jan 2010 | Dec 2009 | Nov 2009 | Oct 2009 | Sep 2009