What do coefficients tell you about the ratio of the reactants

In a balanced chemical equation, the coefficients can be used to determine the relative amount of molecules, formula units, or moles of compounds that participate in the reaction. The coefficients in a balanced equation can be used as molar ratios, which can act as conversion factors to relate the reactants to the products. These conversion factors state the ratio of reactants that react but do not tell exactly how much of each substance is actually involved in the reaction.

The molar ratios identify how many moles of product are formed from a certain amount of reactant, as well as the number of moles of a reactant needed to completely react with a certain amount of another reactant. For example, look at this equation:. In other words, 1 mol of methane will produced 1 mole of carbon dioxide as long as the reaction goes to completion and there is plenty of oxygen present.

These conversion factors state the ratio of reactants that react but do not tell exactly how much of each substance is actually involved in the reaction.

The numbers placed in front of formulas to balance equations are called coefficients, and they multiply all the atoms in a formula. Glucose is a reducing sugar because it belongs to the category of an aldose meaning its open-chain form contains an aldehyde group. Generally, an aldehyde is quite easily oxidized to carboxylic acids. Thus, the presence of a free carbonyl group aldehyde group makes glucose a reducing sugar. Sugars that can be oxidised by mild oxidising agents are called reducing sugars.

A non-reducing sugar is a sugar that is NOT oxidised by mild oxidising agents. So if each coefficient is multiplied by a mole, the balanced chemical equation tells us that 1 mole of nitrogen reacts with 3 moles of hydrogen to produce 2 moles of ammonia.

This is the conventional way to interpret any balanced chemical equation. Finally, if each mole quantity is converted to grams by using the molar mass, we can see that the law of conservation of mass is followed. Mass and the number of atoms must be conserved in any chemical reaction. The number of molecules is not necessarily conserved.

A mole ratio is a conversion factor that relates the amounts in moles of any two substances in a chemical reaction. The numbers in a conversion factor come from the coefficients of the balanced chemical equation.

The following six mole ratios can be written for the ammonia forming reaction above. The coefficients are a ratio. For every two unit of hydrogen molecule, you need one unit of oxygen molecule, and the result is two unit of water molecule. That unit is often the particle itself, whether it's an atom, a metal ion, a more substantial molecule or even a protein or enzyme.

It can also be the volume for ideal gases under the same conditions , the moles used in reaction, or molarity in solution.

Simply remember that the coefficient applies to the item following it as a whole. As long as the ratio between coefficients is the same, you can use any unit that maintains it. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group.