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Question
Explain the terms with examples.
Balanced equation
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Solution
A balanced equation is an equation for a chemical reaction in which the number of atoms for each element in the reaction and the total charge are the same for both the reactants and the products. In other words, the mass and the charge are balanced on both sides of the reaction.
The balanced equation is:
2 Fe2O3 + 3 C → 4 Fe + 3 CO2
Both the left and right sides of the equation have 4 Fe, 6 O, and 3 C atoms. When you balance equations, it's a good idea to check your work by multiplying the subscript of each atom by the coefficient. When no subscript is cited, consider it to be 1. It's also good practice to cite the state of matter of each reactant. This is listed in parentheses immediately following the compound. For example, the earlier reaction could be written as:
2 Fe2O3(s) + 3 C(s) → 4 Fe(s) + 3 CO2(g)
where s indicates a solid and g is a gas state of matter.
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