[whitnos]

I started it, but I'm a little lost. Please guide me with clear explanations on what to do. I'd be very thankful.

Determine by experiment the enthalpy change for the reaction:

Na2CO3 + 2HCl -------> 2NaCl + CO2 + H2O

3.125g Na2CO3 was added to 50cm^3 HCl (2mol dm^-3)

Temp rise= 3.5

a) Calculate the heat change during the reaction:

heat change= mcΔT

= 0.050 kg x 4.3 J x 3.5

= 0.7525 kJ

moles of Na2CO3 used= mass used/mol. mass = 3.074/106

= 0.029 mol

Enthalpy change= 0.725/0.029 = 25.948 kj/mol

b) With reference to the volume of HCl, the mass of Na2Co3 and the equation for the reaction, show which of the reagents (HCL or Na2CO3) was in excess.

c) Calculate ΔH1 for the following reaction:

Na2CO3 + 2HCl -------> 2NaCl +CO2+H2O