You mix 125 mL of 0.170 M with 50.0 mL of 0.425 M in a coffee-cup calorimeter, and the temperature of both solutions rises from 20.20 °C before mixing to 22.17 °C after the reaction. What is the enthalpy of reaction per mole of ? Assume the densities of the solutions are all 1.00 g/mL, and the specific heat capacities of the solutions are 4.2 J/g · K. Enthalpy of reaction = kJ/mol

Here is the correct question

You mix 125 mL of 0.170 M CsOH with 50.0 mL of 0.425 M HF in a coffee-cup calorimeter, and the temperature of both solutions rises from 20.20 °C before mixing to 22.17 °C after the reaction. What is the enthalpy of reaction per mole of ? Assume the densities of the solutions are all 1.00 g/mL, and the specific heat capacities of the solutions are 4.2 J/g · K. Enthalpy of reaction = kJ/mol

75.059 kJ/mol

Explanation:

The formula for calculating density  is:

Making mass the subject of the formula; we have :

mass = density × volume

which can be rewritten as:

mass of the solution =  density × volume of the solution

= 1.00 g/mL × (125+ 50 ) mL

= 175 g

Specific heat capacity = 4.2 J/g.K

∴ the energy absorbed is = mcΔT

= 175 × 4.2 × (22.17 - 20.00) ° C

= 1594.95 J

= 1.595 J

number of moles of CsOH =  

= 0.2125 mole

Therefore; the enthalpy of the reaction =

=

= 75.059 kJ/mol

the positions which points up in upward carbon and down in downward carbon are axial

and vice versa holds true for equatorial positions

so the correct answer with labelled diagram will be