Related Experiment Video

Updated: Jul 6, 2026

Analysis of Organochlorine Pesticides in a Soil Sample by a Modified QuEChERS Approach Using Ammonium Formate
04:17

Analysis of Organochlorine Pesticides in a Soil Sample by a Modified QuEChERS Approach Using Ammonium Formate

Published on: January 20, 2023

Occurrence and distribution of hexachlorocyclohexane isomers in vegetation samples from a contaminated area

P C Abhilash1, Sarah Jamil, Vandana Singh

  • 1Eco-auditing Group, National Botanical Research Institute, Council of Scientific and Industrial Research, Rana Pratap Marg, Lucknow 226 001, Uttar Pradesh, India.

Chemosphere
|March 11, 2008
PubMed

More Related Videos

Extraction of Organochlorine Pesticides from Plastic Pellets and Plastic Type Analysis10:12

Extraction of Organochlorine Pesticides from Plastic Pellets and Plastic Type Analysis

Published on: July 1, 2017

Determination of 45 Pesticides in Avocado Varieties by the QuEChERS Method and Gas Chromatography-Tandem Mass Spectrometry05:20

Determination of 45 Pesticides in Avocado Varieties by the QuEChERS Method and Gas Chromatography-Tandem Mass Spectrometry

Published on: December 8, 2023

Related Concept Videos

Mass Spectrometry: Cycloalkane Fragmentation01:05

Mass Spectrometry: Cycloalkane Fragmentation

In mass spectrometry, cycloalkanes exhibit distinct fragmentation patterns due to the inherent stability of their molecular ions compared to linear or branched alkanes. The ring structure of cycloalkanes provides additional stability to the molecular ions, often resulting in prominent ion peaks in the mass spectrum.
For example, cyclohexane molecular ions have a mass-to-charge ratio (m/z) of 84, which tends to produce a stronger signal than linear alkanes like hexane. This stability comes from...
Stereoisomerism of Cyclic Compounds02:33

Stereoisomerism of Cyclic Compounds

In this lesson, we delve into the role of ring conformation and its stability, which determines the spatial arrangement and, consequently, the molecular symmetry and stereoisomerism of cyclic compounds. 1,2-Dimethylcyclohexane is used as a case study to evaluate the possible number of stereoisomers. Here, given the multiple (n = 2) chiral centers, there are 2n = 4 possible configurations that lack a plane of symmetry, as the ring skeleton exists in a non-planar chair conformation. In addition,...
Disubstituted Cyclohexanes: cis-trans Isomerism02:37

Disubstituted Cyclohexanes: cis-trans Isomerism

Depending upon the different spatial orientation of the substituents, the disubstituted cycloalkanes exhibit two types of stereoisomers. The cis isomers have the substituents on the same side of the ring, whereas the trans isomers have the substituents on the opposite sides. These stereoisomers exhibit different physical properties and cannot be interconverted without breaking the carbon-carbon bonds.
In cyclohexane, the substituents can occupy different positions generating distinct isomers.
Stability of Substituted Cyclohexanes02:30

Stability of Substituted Cyclohexanes

This lesson discusses the stability of substituted cyclohexanes with a focus on energies of various conformers and the effect of 1,3-diaxial interactions.
The two chair conformations of cyclohexanes undergo rapid interconversion at room temperature. Both forms have identical energies and stabilities, each comprising equal amounts of the equilibrium mixture. Replacing a hydrogen atom with a functional group makes the two conformations energetically non-equivalent.
For example, in...
Mass Spectrometry: Cycloalkene Fragmentation00:54

Mass Spectrometry: Cycloalkene Fragmentation

The molecular ions of cycloalkenes undergo fragmentation via a retro-Diels–Alder reaction.
Mass Spectrometry: Long-Chain Alkane Fragmentation01:18

Mass Spectrometry: Long-Chain Alkane Fragmentation

The molecular ions of linear alkanes prefer to fragment at the carbon-carbon bond away from the end of the chain since the cleavage of an inner bond creates a stable carbocation and a stable radical. Consequently, the mass signals of linear alkanes feature intense peaks in the middle of the mass-to-charge ratio plot with weaker peaks on either end. The fragmentation of each carbon-carbon bond with the release of a methyl group in each splitting leads to prominent peaks in the mass spectra...