When 32.0 mL of 0.560 M H2SO4 is added to 32.0 mL of 1.12 M KOH in a coffee-cup calorimeter at 23.50°C, the temperature rises to 30.17°C. Calculate H of this reaction per mole of H2SO4 and KOH reacted. (Assume that the total volume is the sum of the individual volumes and that the density and specific heat capacity of the solution are the same as for pure water: d = 1.00 g/mL and c = 4.184 J/g×K.)
H per mole of H2SO4 reacted:
? kJ/mol
H per mole of KOH reacted:
? kJ/mol
To calculate the enthalpy change (ΔH) per mole of H2SO4 and KOH reacted, you need to use the equation:
ΔH = q / n
where:
- q is the heat absorbed or released by the reaction (in Joules),
- n is the number of moles of H2SO4 or KOH reacted.
First, let's calculate the heat absorbed or released by the reaction (q). We can use the equation:
q = m * c * ΔT
where:
- m is the mass of the solution (in grams),
- c is the specific heat capacity of the solution (in J/g×K),
- ΔT is the change in temperature of the solution (in Kelvin).
Given that the density of the solution is 1.00 g/mL and the total volume is the sum of the individual volumes (32.0 mL + 32.0 mL), the mass of the solution can be calculated as:
mass = volume * density
mass = (32.0 mL + 32.0 mL) * 1.00 g/mL
Now, let's calculate the change in temperature (ΔT) by subtracting the initial temperature from the final temperature:
ΔT = (final temperature - initial temperature)
Now we have all the necessary information to calculate q.
After calculating the value of q for both H2SO4 and KOH, we can divide it by the number of moles reacted to obtain the enthalpy change per mole of H2SO4 and KOH reacted.
To obtain the number of moles of H2SO4 and KOH reacted, we'll use the following equation:
moles = concentration * volume
where:
- concentration is given in M (mol/L),
- volume is given in L.
Given that the initial volume of each solution is 32.0 mL (which is equal to 0.032 L) and the Molarity (concentration) of H2SO4 is 0.560 M, and KOH is 1.12 M, we can calculate the number of moles of H2SO4 and KOH.
Finally, divide q by the number of moles to calculate the enthalpy change (ΔH) per mole of H2SO4 and KOH reacted.
mass water x specific heat water x (Tfinal-Tinitial) = ??
moles H2SO4 = M xL
moles KOH = M x L
volume of water = 32 mL + 32 mL = 64.0 mL = 64 grams.