Use your value for the heat of neutralization, ∆H, -9490, to determine the amount of heat evolved when 10.00mL of 0.4091 M HCL reacts with 10.00mL of 0.4037 M NaOH.
To determine the amount of heat evolved, you need to use the formula:
q = ∆H * n
where q is the heat evolved (in joules), ∆H is the heat of neutralization (in joules per mole), and n is the number of moles of the limiting reactant.
First, we need to determine the limiting reactant in the given reaction. The balanced equation for the reaction between HCl and NaOH is:
HCl + NaOH → NaCl + H2O
From the balanced equation, we can see that the stoichiometric ratio between HCl and NaOH is 1:1. Therefore, the reactant that is present in a smaller amount will limit the reaction.
To find the limiting reactant, we need to calculate the number of moles of each reactant. We can use the formula:
moles = concentration * volume
For HCl:
moles of HCl = (0.4091 M) * (10.00 mL/1000 mL) = 0.004091 mol
For NaOH:
moles of NaOH = (0.4037 M) * (10.00 mL/1000 mL) = 0.004037 mol
Since both HCl and NaOH have similar number of moles (up to four decimal places), the limiting reactant is the one that has a smaller coefficient in front of its formula in the balanced equation, which is NaOH in this case.
Therefore, we can consider 0.004037 mol of NaOH as the limiting reactant.
Now, plug the values into the formula:
q = ∆H * n
q = -9490 J/mol * 0.004037 mol = -38.33 J
The negative sign indicates that heat is evolved in the reaction.
Therefore, the amount of heat evolved when 10.00 mL of 0.4091 M HCl reacts with 10.00 mL of 0.4037 M NaOH is approximately -38.33 Joules.