Chapter 3 Flashcards
1
Q
What is atomic mass (atomic weight)?
A
The mass of one atom in atomic mass units (amu); based on ¹²C standard.
2
Q
How is percent composition calculated?
A
(mass of element / total molar mass) × 100
3
Q
How do you find the empirical formula from % composition?
A
- Assume 100 g → use % as g
- Convert to moles
- Divide by smallest mole value
- Round or multiply to whole numbers
4
Q
What is stoichiometry?
A
Calculating quantities of reactants or products using balanced chemical equations.
5
Q
What is the limiting reactant?
A
The substance that is used up first and limits the amount of product formed.
6
Q
What do you need to identify the limiting reagent?
A
- Convert both reactants to moles
- Use mole ratio to find which makes less product
7
Q
What is theoretical yield?
A
The maximum amount of product that could form based on limiting reagent.
8
Q
How do you calculate percent yield?
A
(Actual yield / Theoretical yield) × 100%
9
Q
A
