Zadania z chemii IB SL

Describe how the student should prepare this standard solution from the weighed solid using a 250.0 $\mathrm{cm^3}$ volumetric flask.

The student pipetted 25.00 $\mathrm{cm^3}$ of the potassium hydroxide solution into a conical flask and titrated it with nitric acid, $\ce{HNO3(aq)}$, of concentration 0.1250 $\mathrm{mol\,dm^{-3}}$. The burette readings before and after the titration are…

Using the concentration determined in 1c and the intended concentration of 0.1500 $\mathrm{mol\,dm^{-3}}$, calculate the percentage error in the concentration of the potassium hydroxide solution. If you have no value from 1c, take the concentration to be…

Explain why the potassium hydroxide solution has to be standardized before it is used in the titration. Assume that there are no systematic errors in the procedure.

Titanium is not included in the graph. Use sections 9 and 10 of the data booklet to find its atomic radius and first ionization energy, and annotate the graph with a cross (X) at the position of the data point for titanium.

The data show that the first ionization energy and the atomic radius are related. (i) State what kind of relationship links the two variables. (ii) Compare and contrast the trends observed for the three groups.

(i) Suggest one hazard to health or safety in Student A's procedure. (ii) Student A plotted the highest temperature of each mixture against the volume of nitric acid. With a ruler, draw two straight lines of best fit: one following the rising set of points and…

Student B pipetted 30.00 $\mathrm{cm^3}$ of the potassium hydroxide solution into a 150 $\mathrm{cm^3}$ glass beaker and added the nitric acid from a burette in portions of 4.00 $\mathrm{cm^3}$, recording the steady temperature after each addition. Volume of…

Hexanoic acid, $\ce{CH3(CH2)4COOH}$, is a weak acid. The graph shows how the pH changes during the titration of a 20.0 $\mathrm{cm^3}$ aqueous solution of hexanoic acid with aqueous sodium hydroxide. (i) Deduce an expression for the equilibrium constant, $K$,…