Zadania z chemii IB HL

Portions of the rinse water were then titrated with the standardized EDTA solution in the presence of murexide as indicator. The burette readings are given in the table. Trial 1 Trial 2 Trial 3 Trial 4 Final burette reading / $\mathrm{cm^3}$ (± 0.05…

The cyanide ion acts as a ligand in many complex ions, for example hexacyanoferrate(III), $\ce{[Fe(CN)6]^3-}$. (i) State the type of bond, as precisely as possible, that joins each cyanide ion to the iron ion. (ii) Deduce the oxidation state of iron in…

Each indicator contains more than one benzene ring. (i) State one functional group, other than the phenyl group, that is present in all three indicators. (ii) Deduce the colour of light absorbed by bromothymol blue in acidic conditions and by bromophenol blue…

Draw a line of best fit on the graph, extrapolating it beyond the range of the data.

State, in mathematical terms, how the absorbance of these solutions depends on their concentration.

The colorimeter can record either absorbance or percentage transmittance at a chosen wavelength. Outline why one particular wavelength has to be selected.

Deduce the equation that relates absorbance to concentration for these solutions, including the numerical value of the constant.

Estimate the absorbance of a 0.400 $\mathrm{mol\,dm^{-3}}$ solution of nickel(II) sulfate.

Predict the difference, if any, between the absorbance of the 0.400 $\mathrm{mol\,dm^{-3}}$ solution read from the extrapolated line and the value calculated from the equation in 3d.