When 4.51 g of cacl2 dissolved in 50.00 ml of water in a coffee cup calorimeter, the temperature of the solution rose from 22.6â°c to 25.8â°c.
specific heat of the solution is equal to the specific heat of water = 4.18 j/gâºc.
density of the solution is equal to the density of water = 1.00 g/ml.

what is qsolution?

what is qreaction ?

what is îhrxn in kj/mol of cacl2 ?

Explanation:

The heat gained by the solution = q

where,

q = heat gained = ?

c = specific heat of solution=

Mass of the solution(m) = mass of water + mass of calcium chloride

Mass of water = ?

Volume of water = 50.00 mL

Density of water = 1.00 g/mL

Mass = Density × Volume

m = 1.00 g/mL × 50.00 mL = 50.00 g

Mass of the solution (m) = 50.00 g + 4.51 g =54.51 g

= final temperature =

= initial temperature =

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

The heat gained by the solution is 729.126 J.

Heat energy released during the reaction  = q'

q' = -q  ( law of conservation of energy)

q' = -729.126 J

The heat energy released during the reaction is -729.126 J.

Moles of calcium chloride, n =

The ΔH of the reaction is -17.945 kJ/mol.

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