Intro to Moles & Stoichiometry

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What is a mole in chemistry?

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A mole is a unit of measurement used to express the amount of a substance. It is defined as the amount of substance that contains as many entities (atoms, molecules, etc.) as there are in 12 grams of carbon-12.

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What is stoichiometry?

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Stoichiometry is the branch of chemistry that deals with the calculation of reactants and products in chemical reactions based on the conservation of mass.

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What is the molar mass of a substance?

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The molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It is calculated by summing the atomic masses of all atoms in the molecular formula.

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How do you calculate the number of moles from mass?

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Number of moles = mass (g) / molar mass (g/mol).

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What is the empirical formula?

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The empirical formula is the simplest whole-number ratio of atoms of each element in a compound.

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What is the molecular formula?

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The molecular formula shows the actual number of atoms of each element in a molecule of a compound.

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How do you determine the molecular formula from the empirical formula?

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To find the molecular formula, divide the molecular molar mass by the empirical formula mass and multiply the subscripts in the empirical formula by that ratio.

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What is the balanced equation for the combustion of B2H6?

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B2H6 + 3O2 → 2HBO2 + 2H2O.

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What is the mole ratio in a balanced chemical equation?

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The mole ratio is the ratio of the coefficients of the reactants and products in a balanced chemical equation, used to convert between moles of different substances.

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What is the significance of the coefficients in a balanced equation?

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Coefficients indicate the number of moles of each substance involved in the reaction.