MOJZA`
AS Chemistry Formulas
Atoms, Molecules and Stoichiometry
𝑀𝑎𝑠𝑠
-Moles: 𝑀𝑜𝑙𝑎𝑟 𝑀𝑎𝑠𝑠
-Moles:
𝑉𝑜𝑙𝑢𝑚𝑒
24
-Volume of a gas: Moles ✕ 24
𝑃𝑒𝑎𝑘 𝐻𝑒𝑖𝑔ℎ𝑡
-Heat Capacity formula:
Q=mcΔT
Q is heat energy,
m is mass,
c is specific heat capacity
ΔT is change in temperature
-Average bond enthalpy:
𝚺Bond enthalpy in reactants- 𝚺Bond
enthalpy in products
-Moles: concentration ✕ volume
-Relative abundance: 𝑇𝑜𝑡𝑎𝑙 𝐻𝑒𝑖𝑔ℎ𝑡 ×
Chemical Energetics
100
Equilibria
-Ar:(mass ✕ relative abundance)/100
Kp: [product]n/[reactant]n (gases only)
-Molecular formula: (empirical formula) ✕ n
Kc: [product]n/[reactant]n (liquid and
gases only)
𝑀𝑜𝑙𝑒𝑐𝑢𝑙𝑎𝑟 𝑀𝑎𝑠𝑠
where n: 𝑀𝑎𝑠𝑠 𝑜𝑓 𝐸𝑚𝑝𝑖𝑟𝑖𝑐𝑎𝑙 𝐹𝑜𝑟𝑚𝑢𝑙𝑎
-Percentage composition:
𝐴𝑡𝑜𝑚𝑖𝑐 𝑚𝑎𝑠𝑠× 𝑁𝑜. 𝑜𝑓 𝑚𝑜𝑙𝑎𝑟 𝑚𝑜𝑙𝑒𝑠
𝑀𝑜𝑙𝑎𝑟 𝑚𝑎𝑠𝑠 𝑜𝑓 𝐶𝑜𝑚𝑝𝑜𝑢𝑛𝑑
× 100
Where n = no. of moles in equation
𝑀𝑜𝑙𝑒 𝑜𝑓 𝑂𝑛𝑒 𝐺𝑎𝑠
-Mole fraction: 𝑇𝑜𝑡𝑎𝑙 𝑀𝑜𝑙𝑒 𝑜𝑓 𝐺𝑎𝑠
States of Matter
-Partial pressure of a gas: mole fraction
✕ total pressure
-Ideal Gas Law: PV = nRT
-Variation of Ideal Gas Law to find Mr:
-Combined gas law:
𝑃1𝑉1
:
𝑡1
𝑀𝑎𝑠𝑠 × 𝑅𝑇
𝑃𝑉
𝑃2𝑉2
𝑡2
0