When 10.0 g of ammonium nitrate (molar mass= 80 g/mol) are dissolved in 1.00 L of water in a bomb calorimeter with a heat capacity of 2.30 kJ/ K, the temp drops 1.52 K. What is the molar enthalpy of solution of ammonium nitrate?
q = Ccal x delta T
q/gram = q/10 g
q/mol = (q/10g) x molar mass NH4NO3
To determine the molar enthalpy of solution of ammonium nitrate, we can use the equation:
ΔH = q / n
where ΔH is the molar enthalpy of solution, q is the heat transferred, and n is the number of moles of ammonium nitrate.
First, let's find the heat transferred (q). We can use the equation:
q = CΔT
where C is the heat capacity of the bomb calorimeter and ΔT is the change in temperature. Substituting the given values, we have:
q = 2.30 kJ/K * (-1.52 K) = -3.50 kJ
Next, let's calculate the number of moles of ammonium nitrate (n). We can use the equation:
n = mass / molar mass
where mass is the mass of ammonium nitrate and molar mass is the molar mass of ammonium nitrate. Substituting the given values, we have:
n = 10.0 g / 80 g/mol = 0.125 mol
Now, we can substitute the calculated values into the first equation to find the molar enthalpy of solution (ΔH):
ΔH = q / n = -3.50 kJ / 0.125 mol = -28.0 kJ/mol
Therefore, the molar enthalpy of solution of ammonium nitrate is -28.0 kJ/mol.