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Question	Answer
Why do –NH2 and –NR2 and –OH change colour of a chromophore?	All have lone pairs of electrons that become involved in delocalised system
Axis of a UV-visible spectrum	x axis is wavelength (nm); y axis is intensity of absorbance (usually no units)
Axis of an IR spectrum	x axis is wave number (cm-1); y axis is transmittance (%)
Why are there many shades of blue?	Shade depends on what other colours (frequencies) are absorbed apart from red
As size of conjugated system increases	absorption is more intense and the wavelength of λmax increases (excitation energy gap decreases)
Principles of green chemistry	minimise waste, reduce feedstock consumption, and reduce energy consumption
How would you analyse the fatty acids in a triester?	Heat with conc NaOH to hydrolyse, add dilute HCl to release free acid from the salt, then analyse using g.l.c. (methyl esters often used instead of the fatty acid as more volatile- shorter retention time)
What additional info is obtained by adding a mass spectrometer to a g.l.c. instrument?	Relative molecular mass of each component

Resource summary

	Created by joannalivesey over 10 years ago