water of crystallisation
What water of crystallisation means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of water of crystallisation
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Reference: AQA
The water shown after the dot in a hydrated formula, whose mass must be included in the calculation.
The fixed amount of water built into a crystal lattice, written after a dot as in CuSO₄·5H₂O.
Topics that use water of crystallisation
- Relative atomic mass and relative molecular mass (AQA A-Level)
- Amount of substance (OCR A-Level)
Related terms
- amount of substance
- atom economy
- Atom economy and by-products
- Concentration in mol dm⁻³
- Converting between cm³ and dm³
- Converting between moles and number of particles
- Empirical formula
- Empirical formula mass and molecular formula multiplier
Using water of crystallisation in the exam
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