[NOTES] Chapter 3: Stoichiometry of Formulas and Equations Flashcards
Mole (mol)
SI unit for amount of substance
- the amount of substance that contains the same number of entities as the number of atoms in 12 g of carbon-12
Molar Mass
The mass of a mole of its entities (atoms, molecules, or fomula units) and has units of grams per mole (g/mol)
Empirical Formula
Derived from mass analysis and shows the lowest whole number of moles and thus the relative number of atoms of each element in the compound
Molecular Formula
Shows the actual number of atoms of each element in a molecule
Structural Formula
Shows the relative placement and connections of atoms in a molecule
Reactants
The substances present before the change
Products
The substances produced during the change
Balancing (stoichiometric) Coefficient
A numerical multiplier of all the atoms int he formula that follows it
- Start with the most complex substance, the one with the largest number of different types of atoms
- End with the least complex substance, such as the element itself
Limiting Reactant (or Limiting Reagent)
A substance which is fully absorbed when the chemical reaction is complete. This reagent limits the amount of the product generated and the reaction cannot continue without it
Theoretical Yield
The amount of product calculated from the molar ratio in the balanced equation
Side Reactions
A chemical reaction that occurs at the same time as the actual main reaction, but to a lesser extent
Actual Yield
Given these reasons for obtaining less than the theoretical yield, the amount of product actually obtained is this
Percent Yield
The actual yield expressed as a percentage of the theoretical yield
% yield = (actual/theoretical) x 100
Green Chemistry
Academic, Industrial, and Government chemists develop methods that reduce or prevent the release of harmful substances into the environment and the wasting of energy resources
