If the reactants have a potential energy of 10.2 kJ/mol and the products have a potential

energy of 15.7 kJ/mol, what is AH?

The ΔH is 5.5 kJ/mol and the reaction is endothermic.

Explanation:

To calculate the ∆H (heat of reaction) of the combustion reaction, that is, the heat that accompanies the entire reaction, you must make the total sum of all the heats of the products and of the reagents affected by their stoichiometric coefficient ( number of molecules of each compound participating in the reaction) and finally subtract them:

Combustion enthalpy = ΔH = ∑H products - ∑Hreactants

In this case:

ΔH = 15.7 kJ/mol - 10.2 kJ/mol= 5.5 kJ/mol

An endothermic reaction is one whose enthalpy value is positive, that is, the system absorbs heat from the environment (ΔH> 0).

The ΔH is 5.5 kJ/mol and the reaction is endothermic.

c

explanation:

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol