Two solutions, initially at 24.69°c, are mixed in a coffee cup calorimeter (ccal = 105.5 j/°c). when a 200.0 ml volume of 0.100 m agno3 solution is mixed with a 100.0 ml sample of 0.100 m nacl solution, the temperature in the calorimeter rises to 25.16°c. determine the dh°rxn, in units of kj/mol agcl. assume that the density and heat capacity of the solutions is the same as that of water.

a. -78 kj/mol agcl
b. -25 kj/mol agcl
c. -64 kj/mol agcl
d. -32 kj/mol agcl
e. -59 kj/mol agcl

The correct answer is option c.

Explanation:

Specific heat of water =  4.18 J/g°C

Density of water = 1 g/ml

Mass of solution ,m'=

Mass of solution ,m''=

Since NaCl solution is present in lessor mass so, it will act limiting reagent.

Heat absorbed by the solution

Heat absorbed by the calorimeter ,

Heat released during reaction,=49.585 J+589.38 J=638.965 J

As we know that NaCl is present as limiting reagent, the product will form according to the availability of NaCl.

Moles of NaCl in 100.0 ml of 0.100 solution = 0.01 moles

1 mol of NaCl gives 1 mol of AgCl, then 0.01 mol of NaCl will give 0.01 mol of AgCl

Heat of the reaction per 1 mol of AgCl =

The heat released during the reaction that exothermic reaction's is negative.

Hence the correct answer is option c.