Two different kettles are used to heat water, as shown in Fig. 3.1. [Figure 3.1] Data for the two kettles is shown in Fig. 3.2. [Figure 3.2] | | energy supplied to the kettle in one minute/J | thermal energy (heat) supplied by the kettle to the water in one minute/J | |---|---|---| | electric kettle | 120000 | 95000 | | gas heated kettle | 130000 | 90 000 |

1. (a)(i)Calculate the efficiency of the electric kettle. efficiency =[2]
2. (a)(ii)Calculate the useful power of the gas heated kettle. power =[2]
3. (b)Both kettles contain the same mass of water, at the same initial temperature. State and explain which kettle brings the water to boiling point first.[1]
4. (c)The boiling water produces steam at 100°C. State one difference between molecules in the steam and molecules in the boiling water.[1]

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