topic 10: organic, halogenoalkanes, alcohols, spectra

Question 1

how do isotopes affect the peaks observed in a mass spectrum

Answer 1

isotopes create additional peaks. for ex M+1 peak results from the presence of a C13 isotope

Question 2

3 signifcances of heating under reflux in organic chem

Answer 2

allows reactions at solven’ts bp without losing volatite reactants/products
provides constant temp for consistent reactions
enables longer reaction times to increase product yeild

Question 3

how cna fragmentraiton help dtermine the strucutre of an roganic compound in mass spectrometry

Answer 3

by analysizing m/z values of fragment ions, u can peice together the strucutre.

Question 4

diff between hoolytic bond breaking and heterolytic bond breaking

Answer 4

homolytic- each atoms keeps one eldctron, forming raidcals
heterolytic - one atoms keeps both electrons forming ions

Question 5

y is drying important in the purification of organic liquids

Answer 5

dryinf removes water, an impurity from aqoues reagents

Question 6

wt happens to a primary alcohol when its oxidised

Answer 6

it becomes an aldehyde, then a carboxlylic acid

Question 7

wt distingushes primary alcohols from secondary and teritrary alcohols in terms of oxidaiotn reactions

Answer 7

primary alcohols oxidize to aldehydes, then carboxlyic acids
secondary alcohols oxidize to ketones
teritary alcohols dont oxidize easily

Question 8

wt mkaes halogenoalkanes reactive compared to hydrocarbons

Answer 8

halogenoalaknes r more reactive than hydrocarbons cuz of the polar C-X bond, the carbon atom attracts nuclephiles due to its partial postive charge

Question 9

wt types of reactions can alcohols undergo

Answer 9

combusitons
halogenation
dehydration to alkenes

Question 10

general formula for halogenoalaknes

Answer 10

CnH2n+1

Question 11

wt techniques r used to maximise yeild of diff products during oxidation reactions

Answer 11

heating under reflux - for full oxidation to acids/ketones
distillation with addition - for partial oxidation to aldehydes

Question 12

wt types of compounds r commonly used as drying agents for organic liquids

Answer 12

magnesium sulfate
sodium sulfate
calcium chloride

Question 13

how does bromination differ from chlornation when converting alcohols to halogenoalknaes

Answer 13

bromination needs acid catalyst
chlorination needs heat