A 50W heating coil is totally immersed in 100g of water contained in an insulated flask of negligible heat capacity. The initial temperature of water...

A 50W heating coil is totally immersed in 100g of water contained in an insulated flask of negligible heat capacity. The initial temperature of water in the flask is 20^oc.
i) Determine how long it takes for the water to boil at 100^oC when the heater is switched on
ii) After the water has been boiling for 15 minutes, it is found that the mass of water in the flask has decreased to 80g. Assuming no external heat losses, calculate a value for the specific latent heat of vaporization of water

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Kavungya answered the question on May 31, 2019 at 10:09

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