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CAIE IGCSE Chemistry 11.1.7 Structural formula is an unambiguous

CAIE IGCSE Chemistry 11.1.7 Structural formula is an unambiguous
Cambridge IGCSE Chemistry 0620 syllabus for exams in 2026, 2027 and 20282026–2028

Practise recognising structural formulae such as HCOOH or CH3CH=CH2 and using them to show how atoms are arranged in molecules.

How this is tested

  • interpret condensed structural formulae to show the arrangement of atoms in a molecule

Question 4(a)(i)

[Maximum number: 1]

The equation for the reaction between methanoic acid and ethanol in the presence of a catalyst can be represented as shown.

HCOOH+CH3CH2OH⇌X+H2OΔH=−29.5 kJ/mol\mathrm{HCOOH}+\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH} \rightleftharpoons \mathbf{X}+\mathrm{H}_{2} \mathrm{O} \quad \Delta H=-29.5 \mathrm{~kJ} / \mathrm{mol}

X represents the ester formed.

In the equation, methanoic acid is represented by the formula HCOOH .

Name this type of formula.