Interpret the functional group region of an IR spectrum by matching absorption bands to bond types (O-H, C=O, C-H, N-H, C=C) with the wavenumber table in the data booklet, and use the spectrum to confirm or rule out functional groups.
(i) Determine the molecular formula and the empirical formula of cresolphthalein. (ii) A simplified infrared (IR) spectrum of cresolphthalein is shown below. State the bonds responsible for the absorptions labelled P, Q and R. Use section 20 of the data…
The mass spectrum of carbonyl dibromide is shown below. Bromine has two isotopes, and , of almost equal abundance. (i) Explain the origin of the peaks that appear at m/z values smaller than those of the molecular ion. (ii) Deduce…
What is a limitation of infrared (IR) spectroscopy in determining the structure of an organic compound? A. The sample is destroyed during the analysis B. Structural isomers containing the same functional groups give very similar spectra C. It cannot detect…
Below is the infrared spectrum recorded for ester Y. (i) This spectrum contains two peaks that confirm Y is an ester. Deduce their identity, giving the wavenumber and the bond responsible for each. Use section 20 of the data booklet. (ii) Alcohols and…
Iodoethane can react with aqueous hydroxide ions to produce ethanol. (i) State what type of reaction this is. (ii) Using curly arrows to show the movement of electron pairs, sketch the mechanism of this…
The IR spectrum of HA is shown. Two absorption bands are labelled: Y is a very broad band centred near and Z is a band of medium intensity near . (i) Using section 20 of the data booklet, identify the functional…
(i) Draw the structural formula of 2-chloropentane and that of the structural isomer in which the chlorine atom is attached to a tertiary carbon atom. (ii) Only one of the two isomers drawn in (c)(i) is chiral. Draw stereochemical formulas showing its two…
Methane, carbon dioxide and water vapour are all greenhouse gases. Which property do these gases share that makes them greenhouse gases? A. They absorb the ultraviolet part of solar radiation before it reaches the Earth's surface. B. They are all produced only…