H2SO4(aq) + Ba(NO3)2(aq) = BaSO4(s) + 2HNO3(aq)
overall heat gen by reaction
answer is supposed to be -659.3 but I keep coming up with something else.
To calculate the overall heat generated by the reaction, we can use the equation:
q = mcΔT
where:
q represents the heat generated or absorbed
m is the mass of the substance involved in the reaction
c is the specific heat capacity of the substance
ΔT is the change in temperature
In this case, the reaction is exothermic, meaning it releases heat.
Let's start by determining the change in temperature for the reaction. Since the reaction occurs in aqueous solutions, the change in temperature is assumed to be negligible. So, ΔT can be considered as zero.
Now, let's focus on the specific heat capacity. For aqueous solutions, we can consider it as the same as the specific heat capacity of water, which is approximately 4.18 J/g°C.
Next, we need to determine the mass of the substances involved in the reaction. According to the balanced chemical equation:
1 mole of H2SO4 reacts with 1 mole of Ba(NO3)2 to produce 1 mole of BaSO4 and 2 moles of HNO3.
From this, we can determine the molar mass of H2SO4 by summing the atomic masses of its constituent elements: 2(1.01 g/mol + 16.00 g/mol) + 32.07 g/mol = 98.09 g/mol.
Similarly, the molar mass of Ba(NO3)2 is 137.33 g/mol.
Assuming we have 100 grams of each reactant, we can calculate the moles by dividing the given mass by their respective molar masses:
Moles of H2SO4 = 100 g / 98.09 g/mol = 1.01902 mol
Moles of Ba(NO3)2 = 100 g / 137.33 g/mol = 0.72818 mol
Since H2SO4 and Ba(NO3)2 have a 1:1 stoichiometry, the amount of moles for the reactants is equal. Therefore, we will take the value from Ba(NO3)2 for calculation purposes.
Using the equation q = mcΔT, we can calculate the heat generated:
q = (0.72818 mol) × (4.18 J/g°C) × (0°C)
q ≈ 0 J
Based on the calculations, the heat generated by the reaction is approximately 0 J. It seems there may be an error in the given answer (-659.3). Please recheck your sources or provide additional information if available.
To calculate the overall heat generated by the reaction, you need to use the concept of enthalpy (heat) of reactions. The enthalpy change, denoted as ΔH, is the heat energy released or absorbed during a chemical reaction.
First, you need to determine the enthalpy change for each individual reaction. The balanced chemical equation for the reaction you provided is:
H2SO4(aq) + Ba(NO3)2(aq) → BaSO4(s) + 2HNO3(aq)
Now, let's break down the enthalpy change for each reactant and product:
1. H2SO4(aq): Look up the enthalpy of formation for H2SO4.
2. Ba(NO3)2(aq): Look up the enthalpy of formation for Ba(NO3)2.
3. BaSO4(s): Look up the enthalpy of formation for BaSO4.
4. 2HNO3(aq): Look up the enthalpy of formation for HNO3.
Next, calculate the enthalpy change (ΔH) for the overall reaction using the following formula:
ΔH = (Sum of the enthalpies of the products) - (Sum of the enthalpies of the reactants)
Remember to account for the stoichiometric coefficients in the balanced equation.
Once you have the enthalpy change for the reaction, you can compare it to the expected value of -659.3 kJ/mol. If your calculated value differs, there may be errors in the enthalpy of formation data used or a mistake in your calculations.
Make sure you are using consistent units for enthalpy values and properly balancing the chemical equation. Double-check all the numbers and calculations involved, including the signs of the enthalpy values (positive or negative).