What is Delta H rxn for the following chemical reaction?
H2O(l) + CCl4(l)-> COCl2(g) + 2HCl(g)
(products)- (reactants)=delta H
(-403.4 kJ/mol)-(-425.3 kJ/mol)=21.9 kJ
look up deltaHf for each compound, then
DHrxn = (n*DHf products) - (n*DHf products)
Oh, you're asking about Delta H rxn? Well, I like to think of it as the "Delta Hilarious reaction"! In this case, the reactants are H2O (water) and CCl4 (carbon tetrachloride), and they're getting together to form COCl2 (phosgene gas) and 2HCl (hydrochloric acid). Now, let me check my comedy database... I mean, chemical database for the answer to that! *beep boop beep* Ah, here it is! The Delta H rxn for this reaction is approximately -92 kJ/mol. So, not only is this reaction hilarious, it's also quite exothermic! Trust me, it's a real gas!
To find the enthalpy change (ΔHrxn) for the given chemical reaction, we need to subtract the sum of the enthalpies of the reactants from the sum of the enthalpies of the products.
The balanced equation for the reaction is:
H2O(l) + CCl4(l) -> COCl2(g) + 2HCl(g)
The enthalpy change for the reaction can be calculated using the enthalpy of formation (∆Hf) values of the compounds involved.
The values are as follows:
∆Hf(H2O(l)) = -285.8 kJ/mol
∆Hf(CCl4(l)) = -95.7 kJ/mol
∆Hf(COCl2(g)) = -123.5 kJ/mol
∆Hf(HCl(g)) = -92.3 kJ/mol
Now, let's calculate the ΔHrxn:
ΔHrxn = Σ∆Hf(products) - Σ∆Hf(reactants)
Reactants: H2O(l) + CCl4(l)
Products: COCl2(g) + 2HCl(g)
Substituting the values in, we get:
ΔHrxn = [∆Hf(COCl2(g)) + 2 * ∆Hf(HCl(g))] - [∆Hf(H2O(l)) + ∆Hf(CCl4(l))]
= [(-123.5 kJ/mol) + 2 * (-92.3 kJ/mol)] - [(-285.8 kJ/mol) + (-95.7 kJ/mol)]
Simplifying the equation:
ΔHrxn = (-308.1 kJ/mol) - (-381.5 kJ/mol)
= 73.4 kJ/mol
Therefore, the ΔHrxn for the given chemical reaction is 73.4 kJ/mol.
To determine the ΔH_rxn (enthalpy change) for the given chemical reaction, you will need to look up the standard enthalpies of formation (ΔHf) for each species involved in the reaction and use them to calculate the difference between the sum of the products and sum of the reactants.
To find the standard enthalpies of formation, you can refer to a reliable reference source such as a chemistry textbook or online database.
Here are the standard enthalpies of formation for the given species:
ΔHf of H2O(l) = -285.8 kJ/mol
ΔHf of CCl4(l) = -95.7 kJ/mol
ΔHf of COCl2(g) = -220.2 kJ/mol
ΔHf of 2HCl(g) = -92.3 kJ/mol
Now, you can calculate the ΔH_rxn using the following equation:
ΔH_rxn = Σ(ΔHf products) - Σ(ΔHf reactants)
Plug in the values:
ΔH_rxn = [ΔHf(COCl2(g)) + ΔHf(2HCl(g))] - [ΔHf(H2O(l)) + ΔHf(CCl4(l))]
ΔH_rxn = [-220.2 kJ/mol + -92.3 kJ/mol] - [-285.8 kJ/mol + -95.7 kJ/mol]
ΔH_rxn = -312.5 kJ/mol + 381.5 kJ/mol
ΔH_rxn = 69 kJ/mol
Therefore, the ΔH_rxn for the given chemical reaction is 69 kJ/mol.