Question

What is a thermochemical equation? How is this different than a chemical equation? please appreciate typewriting when responding to this question  

Answer 1

Thermochemcial equation

Chemical reaction involve energy changes. These changes can be represented in a standard way called the thermo chemical equation.

A chemcial equation, which gives the heat change(evolved or absorbed) during the reaction is called thermochemcial equation

This equation can be written either by writting the heat evolved or absorbed as a term in the equation

C(s) + O2(g) ----------------- CO2(g) +393.5KJ. It is exothermic reaction

N2(g) +O2(g) + 180.5 KJ -------- 2 NO(g) . It is endthermic reaction

By usning H notation.

H = -ve for exothermic reaction

H = + ve endothermic reaction

C(s) + O2(g) ---------------- CO2(g)    H = - 393.5 KJ

N2(g) + O2(g) ---------------- 2 NO(g)   H = + 180.5 KJ

CHemcial equation

Chemcial reaction is a process in which a substance or substances is changed into one or more substances.

A chemcial equation uses chemcial symbols for to show what happens during a chemical reaction,

for example Metallic Zn and Sulfur reacts when heated to produce Zinc sulfide,

Zn + S -------------- ZnS.

g

n

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