A student determines an approximate value for the density of the glass from which a test-tube is made. The height h and the external diameter d of the test-tube are shown in a full-size diagram of the test-tube in Fig. 1.1.

1. (a)(i)Measure the height h of the test-tube in Fig. 1.1 to the nearest 0.1 cm. h =[1]
2. (a)(ii)Measure the external diameter d of the test-tube in Fig. 1.1. d =[1]
3. (b)The student uses a ruler and two wooden blocks to help obtain an accurate answer for the height h. Fig. 1.2 shows how the student uses the wooden blocks. [Figure 1.2] Explain why it is important for the student to ensure that the blocks are parallel to one another.[1]
4. (c)The shape of the test-tube is approximately a cylinder. Calculate the external volume VE of the test-tube using the equation: VE = 0.79 d² h VE =[1]
5. (d)The student: • fills the test-tube to the top with water • pours the water from the test-tube into a measuring cylinder. Fig. 1.3 shows the measuring cylinder. [Figure 1.3] Record the reading VI on the measuring cylinder. This is the internal volume of the test-tube. VI =[1]
6. (e)Calculate the volume VG of the glass in the test-tube using the equation: VG = VE - VI VG =[1]
7. (f)Suggest one source of inaccuracy in measuring the internal volume of the test-tube VI.[1]
8. (g)(i)The student uses a balance to measure the mass m of the test-tube. Fig. 1.4 shows the reading on the balance. [Figure 1.4] Record m to the nearest gram. m =[1]
9. (g)(ii)Use your results from (g)(i) and (e) to calculate the density ρ of the glass from which the test-tube is made using the equation: ρ = m/VG Give the unit for your answer. ρ = ................................................. unit = .........................[2]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.