deduce the molecular and/or empirical formula of a compound, given its structural, displayed or skeletal formula

describe: (a) the reduction of aldehydes and ketones using NaBH\(_4\) or LiAlH\(_4\) to produce alcohols (b) the reaction of aldehydes and ketones with HCN, KCN as catalyst, and heat to produce hydroxymitriles as exemplified by ethanol and propanone