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**1. Homework Statement**

from the following observations made during an experiment,determine the specific latent heat of vaporisation of water.

initial mass of water 400g

final mass of water 450g

mass of calorimeter 200g

initial temperature of water & calorimeter 16 degrees

final temperature of water & calorimeter 70 degrees

specific heat capacity of water 4200 j/kg degrees

specific heat capacity of calorimeter 420 j/kg degrees

**2. Homework Equations**

Q= m hfg

**3. The Attempt at a Solution**

let suffix s = steam w = water and c = calorimeter

-ms hfg = mw cw delta tw + mc cc delta tc + ms cw delta ts

-50 = 400x4200x(70-16)+200x420x(70-16)+50x4200x(70-100)=88.956x10 6

therefore 50/88.956x10 6 = 562.075 x 10 -9

if someone would be so kind to check if this is right it will be much appreciated.