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    Im a little bit confused with the conditions and regeants of addition of HCN with carbonyl compunds on the edexcel sylabbus.

    I know conditions is ph8, but what is the reagent. Different txtbooks keep saying different things like KCN or HCN (aq), etc.
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    For OCR Salters, addition of HCN to ketones/aldehydes is just in the presence of NaOH to shift the HCN dissociation equilibrium to the right.
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    Either is fine.

    I usually write Nucleophilic substitution/addition with aqueous KCN allowed to reflux where :CN- is the nucleophile.

    Give the full description and you have nothing to lose.
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    The HCN is only used to get cyanide ions. But as HCN is a weak acid it has a low concentration of cyanide ions in water (because the hydrogen ions dissociate in water). So they use alkali metal cyanides instead (such as KCN) because they give a high enough concentration of cyanide ions for the reaction to take place
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    Cyanide addition. CN.also adds to the name of prefixes in organic chemistry. Triple bond formed between C to N, Has covelent bond and Van der Waals intermolecular forces. Effects the delta chage + & - of electronegativity between C and N. Using NMR can predict bonds using mass spectrometry by seeking the vibration between bonds.
    Fun.
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    (Original post by Casshern1456)
    Cyanide addition. CN.also adds to the name of prefixes in organic chemistry. Triple bond formed between C to N, Has covelent bond and Van der Waals intermolecular forces. Effects the delta chage + & - of electronegativity between C and N. Using NMR can predict bonds using mass spectrometry by seeking the vibration between bonds.
    Fun.
    You appear to be talking utterly irrelevant, not to mention partly incorrect... *****.
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    (Original post by cpchem)
    You appear to be talking utterly irrelevant, not to mention partly incorrect... *****.
    Yes I was. sorry. Was revising for an upcoming exam and still not too comfy with some parts of mass spectrometry, namly structural determination and proton NMR spectra.:o:
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    For edexcel, it's: HCN and pH 8.
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    Thanks all
 
 
 
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