Chapter 3 Summary Flashcards
What is stoichiometry?
The study of the quantitative relationships between chemical formulas and chemical equations.
What does the law of conservation of mass state in stoichiometry?
The total mass of the products of a chemical reaction is the same as the total mass of the reactants.
How is a chemical equation balanced?
By placing coefficients in front of the chemical formulas for the reactants and products, not by changing subscripts.
What is a combination reaction?
A reaction in which two reactants combine to form one product
What is a decomposition reaction?
A reaction where a single reactant forms two or more products
What is a combustion reaction?
A reaction where a substance, typically a hydrocarbon, reacts rapidly with oxygen (O₂) to form CO₂ and H₂O.
How is the formula weight of a compound determined?
By summing the atomic weights of the atoms in its formula.
What is Avogadro’s number?
6.02 × 10²³, the number of formula units in a mole of any substance.
How do you determine the molar mass of a substance?
the molar mass equals the formula weight expressed in grams per mole.
How can an empirical formula be determined from percent composition?
By calculating the relative number of moles of each atom in a sample, usually 100 g.
What is a limiting reactant in a chemical reaction?
the reactant that is completely consumed in a reaction, limiting the amount of product formed.
How is the theoretical yield of a reaction determined?.
It is the quantity of product calculated to form when the limiting reactant is fully consumed.
What is percent yield in a reaction?
The actual yield divided by the theoretical yield, converted to a percentage
What is the difference between molecular weight and formula weight?
Molecular weight refers to the formula weight when the formula is a molecular formula
What is the process of combustion analysis used for?
It determines the empirical formulas of compounds containing carbon, hydrogen, and oxygen.
