During an experiment, a student adds 1.23 g of CaO to 200.0 mL of 0.500 M HCl. The student observes a temperature increase of 5.10 °C. Assuming the solution\'s final volume is 200.0 mL, the density if 1.00 g/mL, and the heat capacity is 4.184 J/(g·°C), calculate the heat of the reaction, ΔHrxn.
q = mass H2O x specific heat H2O x delta T.
i know i need to use the equations q=mcdeltaT
and delta H= q/n but i keep getting the wrong answer. also which one is the limiting reactant...
in the equation CaO(s) +2H+(aq)-->Ca^2+(aq)+H2(g)
To calculate the heat of the reaction, ΔHrxn, we can use the formula:
ΔHrxn = q / mol
where q is the heat transferred in the reaction and mol is the number of moles of the limiting reactant.
In this case, CaO is the limiting reactant because it will be completely consumed by the reaction and its moles can be calculated using its molar mass.
Step 1: Calculate the number of moles of CaO:
Molar mass of CaO = 40.08 g/mol + 16.00 g/mol = 56.08 g/mol
moles of CaO = mass of CaO / molar mass of CaO
= 1.23 g / 56.08 g/mol
Step 2: Calculate the heat transferred (q):
q = m × c × ΔT
where m is the mass of the solution, c is the heat capacity, and ΔT is the temperature change.
Step 3: Calculate the mass of the solution:
mass of the solution = volume of the solution × density
= 200.0 mL × 1.00 g/mL
Step 4: Calculate ΔT:
ΔT = temperature increase = 5.10 °C
Step 5: Calculate the heat transferred (q):
q = mass of the solution × c × ΔT
Step 6: Calculate ΔHrxn:
ΔHrxn = q / mol
Now let's plug in the values and calculate the answer.