Random Knowledge Flashcards
Why one complex ion [Co(H2O)6] and [Co(NH3)6] have different colours
Different frequency of light is absorbed by two complexes.
What is a buffer solution?
A solution that minimises its pH when small amount acid, water or base added.
Why dissociation of water is endothermic
kw increases with temperature
Why magnesium sulphate easy to separate by titanium
MgSO4 is soluble
A way to detect if ethanoic acid is reacting with samples.
sweet smelling liquid
What always produces in anhydride reaction?
Ethanoic acid
What is the percentage yield equation?
actual/theoretical x 100
What is the precautions of using ethanol and why?
water bath because ethanol is flammable.
Heat up below the boiling point of ethanol
Why small amount of cold ethanol is added through Buchner funnel
to remove soluble impurities
Define electronegativity
The tendency of an atom to attract a pair of electrons in a covalent bond
State why Si(CH3)4, CCl4 and CDCl3 are used in H NMR
All are inert
TMS ( Si(CH3)4 ) acts as a calibration
CCl4 and CDCl3 are solvents
Properties of CCl4 and CDCl3 in H NMR
They both don’t have hydrogen so won’t be picked up on the NMR
CCl4 is non polar so good solvent for non polar organic molecules
CDCl3 is polar covalent molecule so good solvent for polar organic molecules
Properties of Si(CH3)4 (TMS)
Produces 1 single peak and away from the other signals.
volatile, low bp
