If 45.0 ml of ethanol (density = 0.789 g/ml) initially at 8.0 ∘c is mixed with 45.0 ml of water (density = 1.0 g/ml) initially at 28.6 ∘c in an insulated beaker, what is the final temperature of the mixture, assuming that no heat is lost? (cetoh=2.42j/(g⋅∘

Answer : The final temperature of the mixture is,

Explanation :

First we have to calculate the mass of ethanol and water.

and,

Now we have to calculate the final temperature of the mixture.

In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.

where,

= specific heat of ethanol =

= specific heat of water =

= mass of ethanol = 35.5 g

= mass of water = 45.0 g

= final temperature of mixture = ?

= initial temperature of ethanol =

= initial temperature of water =

Now put all the given values in the above formula, we get:

Therefore, the final temperature of the mixture is,

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