Skip to main content
    Achieve Academy
    All formula sheets
    OCR
    Chemistry
    J248

    OCR GCSE Chemistry Equation Sheet (J248)

    Free OCR GCSE Chemistry equation sheet: open the official OCR (J248) PDF plus all 13 formulas listed by topic, showing which 13 you must memorise.

    13

    Formulas listed

    13

    You must memorise

    0

    Given in the exam

    Official OCR Gateway Chemistry Data Sheet (J248)

    Official OCR PDF

    Open on OCR

    Periodic Table

    Given in the Chemistry exams — interactive version

    Open periodic table

    Moles & Mass

    Number of moles

    Memorise
    n=massMrn = \dfrac{\text{mass}}{M_r}

    M_r = relative formula mass.

    Mass from moles

    Memorise
    mass=nMr\text{mass} = nM_r

    Avogadro's number

    Memorise
    number of particles=n×6.02×1023\text{number of particles} = n \times 6.02 \times 10^{23}

    Percentage by mass of an element

    Memorise
    % by mass=Ar×number of atomsMr×100\%\text{ by mass} = \dfrac{A_r \times \text{number of atoms}}{M_r} \times 100

    Solutions

    Concentration (g/dm³)

    Memorise
    concentration=massvolume\text{concentration} = \dfrac{\text{mass}}{\text{volume}}

    Volume in dm³ (1 dm³ = 1000 cm³).

    Concentration (mol/dm³)

    Memorise
    concentration=molesvolume\text{concentration} = \dfrac{\text{moles}}{\text{volume}}

    Gases

    Volume of a gas at RTP

    Memorise
    volume=24n\text{volume} = 24n

    RTP: 24 dm³ per mole.

    Yield & Economy

    Percentage yield

    Memorise
    % yield=actual masstheoretical mass×100\%\text{ yield} = \dfrac{\text{actual mass}}{\text{theoretical mass}} \times 100

    Atom economy

    Memorise
    % atom economy=Mr of desired producttotal Mr of products×100\%\text{ atom economy} = \dfrac{M_r\ \text{of desired product}}{\text{total }M_r\ \text{of products}} \times 100

    Energy Changes

    Energy change of a reaction (Higher)

    Memorise
    Q=mcΔTQ = mc\Delta T

    Used in calorimetry experiments.

    Rates

    Mean rate of reaction

    Memorise
    mean rate=quantity of reactant usedtime\text{mean rate} = \dfrac{\text{quantity of reactant used}}{\text{time}}

    Mean rate (product formed)

    Memorise
    mean rate=quantity of product formedtime\text{mean rate} = \dfrac{\text{quantity of product formed}}{\text{time}}

    Electrolysis

    Charge in electrolysis (Higher)

    Memorise
    Q=ItQ = \text{It}
    Chemistry revision notesOCR topic by topicOCR past papersPapers and mark schemesPractice questionsExam-style, with solutions

    Other formula sheets

    OCR Maths HigherOCR Maths FoundationOCR PhysicsAQA ChemistryEdexcel ChemistryOCR BiologyOCR Combined Science