(U2) Formulae And Amounts Of A Substance Flashcards
What is empirical formula?
A formula which shows the simplest whole number ratio of atoms of each element in a compound
What is molecular formula?
A formula which shows the actual number of atoms of each element in a molecule
What is meant by molar gas volume?
Give an example.
- The volume of one mole of gas under specified conditions of temperature and pressure
- e.g. 24 dm3 at 20°C (293K) and 1 atm pressure
State the equation for Avogadro’s Law on gases at 20ºC and 1 atm pressure
Volume = number of moles x 24
V = N x 24
dm3 = mol x 24
V
N | 24
What is the equation for percentage yield?
Actual yield / theoretical yield x 100
What is the equation for atom economy?
Mass of desired product / total mass of products x 100
What is the formula for used to determine a hydrocarbon?
CxHy + (X + y/4)O2 —> XCO2 + (y/2)H2O
What is the word equation for determining the volume of oxygen in hydrocarbon combustion reactions?
Volume of oxygen = (initial contraction - volume of CxHy) + volume of CO2