DF 1 - Formulae, Equations and Amount of Substance

Question 1

What is the ideal gas equation?

Answer 1

pV = nRT
p = pressure in Pa
V = volume in m^3
n = number of moles in mol
R = gas constant, 8.314 J mol^-1 K^-1
T = temperature in K

Question 2

How can you predict the yield of a reaction?

Answer 2

4Na + O2 -> 2Na2O
Work out the number of moles of a reactant you have used, for 2g of sodium: 2/23 = 0.087 mol
Multiply by the ratio between the chosen reactant and product: 0.087 x 0.5 = 0.044 mol
Multiply by the Mr of the product: 0.044 x 62 = 2.73g