Chemistry SL Paper 1B, November 2025, TZ3

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.

Suggest what causes the two quantities in the graph to be related in this way.

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…

State the most important property that water must have, with respect to benzoic acid, for it to be a suitable solvent for this recrystallization.

Outline how each of the two by-products is removed from the benzoic acid during the recrystallization. By-product that is almost insoluble in hot water: ... By-product that is much more soluble than benzoic acid: ...

The volume of hot water used to dissolve the crude solid must be chosen carefully. Deduce the effect on the yield or on the purity of the recrystallized benzoic acid of using too much water and of using too little water. Too much water: ... Too little water:…

Chlorinated solvents such as tetrachloromethane, $\ce{CCl4}$, and 1,1,1-trichloroethane, $\ce{CH3CCl3}$, were once common in laboratories, but their production is now restricted by an international agreement. Besides climate change, state the specific…

This half-cell needs an aqueous solution containing $\ce{Ni^2+}$ ions. State the formula of a compound that would supply this solution when dissolved in water.

Describe the setup needed to join the $\ce{Ni^2+}$ | $\ce{Ni}$ half-cell to a second half-cell so that the completed cell lights a bulb.

State the SI-derived unit used to measure the size of the current flowing through the bulb.