Stoichiometry of Formulas and Equations - Vocabulary Flashcards

Vocabulary flashcards covering core definitions and key concepts from Chapter 3: Stoichiometry of Formulas and Equations.

Mole (mol)

The amount of a substance that contains the same number of entities as there are atoms in exactly $12\,\text{g}$ of carbon-12.

Avogadro's Number ($N_A$)

The fundamental constant representing the number of entities in one mole of a substance, equal to $6.022 \times 10^{23}$ entities.

Molar Mass ($\mathcal{M}$)

The mass of one mole of entities (atoms, molecules, or formula units) of a substance, expressed in units of grams per mole ($\text{g/mol}$).

Empirical Formula

The simplest chemical formula for a compound that gives the relative number of atoms of each element present as the lowest whole-number ratio of moles.

Molecular Formula

A chemical formula that specifies the actual number of atoms of each element present in a single molecule of a compound.

Constitutional Isomers

Compounds that share the same molecular formula but have different structural arrangements of atoms, resulting in distinct physical and chemical properties.

Combustion Analysis

A quantitative laboratory technique used to measure the amounts of carbon and hydrogen in a combustible organic compound by reacting it with oxygen gas to yield $CO_2$ and $H_2O$.

Chemical Equation

A representation using chemical formulas and symbols to express the identities and relative quantitative amounts of substances involved in a physical or chemical change.

Mass Percent

The percentage by mass of a specific element in a compound, determined by: $\text{Mass \% of element X} = \frac{\text{moles of X in formula} \times \text{molar mass of X}}{\text{mass of 1 mol of compound}} \times 100\%$.

Limiting Reactant

The reactant in a chemical reaction that is completely consumed first, thereby limiting the maximum amount of product that can form.

Excess Reactant

A reactant that is not completely consumed when a chemical reaction reaches completion, leaving an unreacted portion remaining.

Theoretical Yield

The maximum calculated amount of product obtained from a given amount of reactant based on stoichiometric molar ratios from a balanced chemical equation.

Actual Yield

The amount of product that is experimentally obtained and isolated from a chemical reaction in practice.

Percent Yield

The ratio of the actual yield to the theoretical yield expressed as a percentage: $\% \text{ yield} = \frac{\text{actual yield}}{\text{theoretical yield}} \times 100\%$.

Mole (mol)

The amount of a substance that contains the same number of entities as there are atoms in exactly $12\,g$ of carbon-12.

Avogadro's Number ($N_A$)

The fundamental constant representing the number of entities in one mole of a substance, equal to $6.022 \times 10^{23}$ entities.

Molar Mass ($\mathcal{M}$)

The mass of one mole of entities (atoms, molecules, or formula units) of a substance, expressed in units of grams per mole ($g\,mol^{-1}$).

Empirical Formula

The simplest chemical formula for a compound that gives the relative number of atoms of each element present as the lowest whole-number ratio of moles.

Molecular Formula

A chemical formula that specifies the actual number of atoms of each element present in a single molecule of a compound.

Constitutional Isomers

Compounds that share the same molecular formula but have different structural arrangements of atoms, resulting in distinct physical and chemical properties.

Combustion Analysis

A quantitative laboratory technique used to measure the amounts of carbon and hydrogen in a combustible organic compound by reacting it with oxygen gas to yield $CO<em>2$ and $H</em>2O$.

Chemical Equation

A representation using chemical formulas and symbols to express the identities and relative quantitative amounts of substances involved in a physical or chemical change.

Mass Percent

The percentage by mass of a specific element in a compound, determined by: $\text{Mass \% of element X} = \frac{\text{moles of X in formula} \times \text{molar mass of X}}{\text{mass of 1 mol of compound}} \times 100\%$.

Limiting Reactant

The reactant in a chemical reaction that is completely consumed first, thereby limiting the maximum amount of product that can form.

Excess Reactant

A reactant that is not completely consumed when a chemical reaction reaches completion, leaving an unreacted portion remaining.

Theoretical Yield

The maximum calculated amount of product obtained from a given amount of reactant based on stoichiometric molar ratios from a balanced chemical equation.

Actual Yield

The amount of product that is experimentally obtained and isolated from a chemical reaction in practice.

Percent Yield

The ratio of the actual yield to the theoretical yield expressed as a percentage: $\% \text{ yield} = \frac{\text{actual yield}}{\text{theoretical yield}} \times 100\%$.

Table 3.1: Chemical Formula of Glucose ($C<em>6H</em>{12}O_6$)

A table detailing the relationship between atoms, moles, atomic masses, and mass per mole of glucose: 6 moles of Carbon ($72.06\,g$), 12 moles of Hydrogen ($12.10\,g$), and 6 moles of Oxygen ($96.00\,g$), giving a total molar mass of $180.16\,g\,mol^{-1}$.

Table 3.2: Compounds with Empirical Formula $CH_2O$

A table listing compounds sharing the empirical formula $CH_2O$ ($40.0\%$ Carbon, $6.71\%$ Hydrogen, $53.3\%$ Oxygen) by whole-number multiple ($n$) and molar mass ($\mathcal{M}$): Formaldehyde ($n=1$, $30.03\,g\,mol^{-1}$), Acetic acid ($n=2$, $60.05\,g\,mol^{-1}$), Lactic acid ($n=3$, $90.09\,g\,mol^{-1}$), Erythrose ($n=4$, $120.10\,g\,mol^{-1}$), Ribose ($n=5$, $150.13\,g\,mol^{-1}$), and Glucose ($n=6$, $180.16\,g\,mol^{-1}$).

Table 3.3: Information Contained in a Balanced Equation

A table demonstrating stoichiometric equivalents using the combustion of propane ($C<em>3H</em>8(g) + 5O<em>2(g) \rightarrow 3CO</em>2(g) + 4H<em>2O(g)$): 1 mole $C</em>3H<em>8$ reacts with 5 moles $O</em>2$ to produce 3 moles $CO<em>2$ and 4 moles $H</em>2O$, maintaining total mass conservation ($44.09\,g$ $C<em>3H</em>8$ + $160.00\,g$ $O<em>2$ $\rightarrow$ $132.03\,g$ $CO</em>2$ + $72.06\,g$ $H_2O$, totaling $204.09\,g$).