Fig. 4.1 shows a mercury-in-glass thermometer made using a glass capillary tube. [Figure 4.1]

1. (a)Describe how to check that the 100°C mark is in the correct position on the thermometer.[3]
2. (b)Some thermometers contain ethanol instead of mercury. A second glass capillary tube is identical to the tube in Fig. 4.1, except that it has no markings on the glass. This tube is used to make an ethanol-in-glass thermometer. The volume of the ethanol in this thermometer is equal to the volume of mercury in the thermometer in Fig. 4.1. The thermal expansion of ethanol is more than that of mercury. State and explain how the maximum possible range of the ethanol-in-glass thermometer differs from the range of the thermometer in Fig. 4.1.[2]

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