The given question is incomplete. The complete question is
The thermite reaction, in which powdered aluminum reacts with iron oxide, is highly exothermic:
. Use standard enthalpies of formation to find ΔH∘rxn for the thermite reaction. Express the heat of the reaction in kilojoules to four significant figures.
Answer: ΔH∘rxn for the thermite reaction is -851.5 kJ
Explanation:
The balanced chemical reaction is :

We have to calculate the enthalpy of reaction
.

![\Delta H^o=[n_{Fe}\times \Delta H_f^0_{(Fe)}+n_{Al_2O_3}\times \Delta H_f^0_{(Al_2O_3)}]-[n_{Al}\times \Delta H_f^0_(Al)+n_{Fe_2O_3}\times \Delta H_f^0_{(Fe_2O_3)}]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo%3D%5Bn_%7BFe%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28Fe%29%7D%2Bn_%7BAl_2O_3%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28Al_2O_3%29%7D%5D-%5Bn_%7BAl%7D%5Ctimes%20%5CDelta%20H_f%5E0_%28Al%29%2Bn_%7BFe_2O_3%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28Fe_2O_3%29%7D%5D)
where,
We are given:

Putting values in above equation, we get:
![\Delta H^o_{rxn}=[(2\times 0)+(1\times -1675.5)]-[(2\times 0)+(1\times -824.2)]=-851.5kJ](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B%282%5Ctimes%200%29%2B%281%5Ctimes%20-1675.5%29%5D-%5B%282%5Ctimes%200%29%2B%281%5Ctimes%20-824.2%29%5D%3D-851.5kJ)
ΔH∘rxn for the thermite reaction is -851.5 kJ
It would have to be all elements in the same family, so since potassium is an Alkali Metal the similar chemicals would be...Lithium, Sodium, Rubidium, Cesium, Francium.
Answer:
Explanation:
Un ácido de Lewis es una especie química que contiene un orbital vacío que es capaz de aceptar un par de electrones de una base de Lewis para formar un aducto de Lewis
Answer:
There are many different types of preservatives like Benzoic acid, Calcium Sorbate, Erythorbic Acid, Potassium Nitrate and Sodium Benzoate. Some act like antioxidants used for slowing down spoilage like Ascorbyl Palmitate, Butylated Hydroxy anisole (BHA) and Butylated Hydroxytoluene (BHT