Answer:
ΔH = -98 kJ/mol
Explanation:
<u>To calculate the heat change of the reaction:</u>
HCl(aq) + NH₃(aq) → NH₄Cl(aq)
0.2M 0.2M ΔT=2.34°C
1x10²mL 1x10²mL
<u>We need to use the next equation:</u>
(1)
<em>where </em><em>q: the amount of heat energy lost or gained</em><em>, </em><em>m: the mass of the substance, c: the specific heat capacity of the substance and ΔT: the change in temperature of the substance </em>
<u>Assuming that the densities of the solutions are the same as for water, we can determine the mass of the solution:</u>
<em>where </em><em>d: density, m: mass and V: volume of solution</em><em> </em><em>= 100 + 100 = 200mL</em><em> </em>
<u>Now, using the calculated mass in equation</u><u> (1)</u><u>, and assuming that the specific heats of the solutions are the same as for water, we can find heat change of the reaction</u>:
This heat is negative because is the heat lost by the reacting HCl and NH₃ and gained by the water, so:
<u>To calculate the heat change of the reaction per mole of HCl, we need to divide the heat change by the number of moles, which is called the enthalpy of reaction:</u>
So, the heat change of the reaction per mole of HCl reacted, often called enthalpy of reaction, is ΔH = -98 kJ/mol.
Have a nice day!