ionic equations
What ionic equations means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of ionic equations
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Reference: OCR
Equations that show only the species that change, by splitting soluble ionic compounds into their ions and keeping insoluble solids, gases and water together.
The balanced equation CO₃²⁻(aq) + 2H⁺(aq) → CO₂(g) + H₂O(l) shows two hydrogen ions needed for each carbonate ion, with charges balancing to zero.
Chlorine added to aqueous sodium bromide gives Cl₂ + 2Br⁻ → 2Cl⁻ + Br₂, and with aqueous sodium iodide gives Cl₂ + 2I⁻ → 2Cl⁻ + I₂.
Shows only the species that actually change, with spectator ions cancelled from both sides.
Topics that use ionic equations
- Balanced equations and associated calculations (AQA A-Level)
- Trends in properties (AQA A-Level)
- Compounds, formulae and equations (OCR A-Level)
- The periodic table - 3.1.4 Qualitative analysis (OCR A-Level)
Related terms
- silver halide colours
- acidifying with nitric acid
- Ammonium ion identification
- Anion identification
- Balanced chemical equations
- Characteristic reactions
- charge balance
- choice of acid
Using ionic equations in the exam
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