amount of substance Flashcards
(27 cards)
What is a mole?
The amount of substance that contains 6.022 × 10²³ particles (Avogadro’s number).
What is Avogadro’s constant?
6.022×10²³
What is molar mass?
The mass of one mole of a substance in grams (g/mol).
What is the empirical formula?
The simplest whole number ratio of atoms in a compound.
What is the molecular formula?
The actual number of atoms of each element in a molecule.
What is the equation linking moles
mass
What is the equation linking moles
concentration
How do you convert cm³ to dm³?
Divide by 1000
What is the equation for gas volume at RTP?
Volume = moles × 24 (RTP = 24.0 dm³/mol)
What is the ideal gas equation?
pV = nRT
What does each symbol mean in pV = nRT?
p = pressure (Pa)
What is the equation for % yield?
Percentage yield = actual yield / theoretical yield × 100
What is the equation for atom economy?
Atom economy = mass of desired product / total mass of reactants × 100
How do you convert cm³ to dm³?
1000 cm³ = 1 dm³
How do you convert dm³ to m³?
1000 dm³ = 1 m³
How do you convert °C to K?
K = °C + 273
How do you convert kPa to Pa?
1 kPa = 1000 Pa
How do you convert g to kg?
1 g = 0.001 kg
How do you calculate the empirical formula?
Divide each element’s mass or % by its Ar → Divide by smallest → Multiply to get whole numbers
How do you calculate the molecular formula from the empirical formula?
Molecular formula = Empirical formula × (Mr / Empirical Mr)
Why is atom economy important?
It shows how efficiently reactants are converted to useful products → sustainability & cost-effectiveness.
Why is percentage yield usually less than 100%?
Incomplete reactions
What is the molar volume of a gas at RTP?
24.0 dm³/mol
Why must volume be in m³ in the ideal gas equation?
Because the gas constant R = 8.31 uses SI units
