Fill in Table 2.1 by taking the readings for 10.0 cm^3 and 35.0 cm^3 from Fig. 2.1, then subtracting the initial temperature of X from each one to find the temperature change. All temperatures and temperature changes should be written to +/- 0.5^{\circ}C.
On Fig. 2.2, draw a graph of temperature change (y-axis) against the volume of Y (x-axis). Draw a line of best fit through the points where the temperature change rises. Draw another line of best fit through the points where the temperature change falls. Continue both lines until they cross.
Locate the point where the two lines meet on the graph. Work out the volume of Y at this point.
Y is 2.0 mol/dm^3 potassium hydroxide. Potassium hydroxide has the formula KOH. Calculate the number of moles of hydroxide ions, OH^-, in the volume of Y in (c).
The volume of Y in (c) is the amount needed to neutralise 25.0 cm^3 of X completely. Use your answer to (d) to calculate the concentration of hydrogen ions, H^+, in X. $\mathrm{H^+ + OH^- \rightarrow H_2O}$
Suggest why 25 cm^3 of X is measured with a volumetric pipette rather than a measuring cylinder.
Suggest why the mixture is stirred in step 6.