0654.B11.1.03 — Describe the differences in composition 6 Explain the differences in composition between inspired and expired air, limited to: between inspi: past paper questions

Real questions on 0654.b11.1.03 — describe the differences in composition 6 explain the differences in composition between inspired and expired air, limited to: between inspi

The newest 8 of 8 written questions. Open one to see it on the real paper.

1. 0654/32 · February/March 2026 · Q2a(ii)[1]

   Table 2.1 shows how the percentage of gases X, Y and Z changes in inspired air compared to expired air. Table 2.1 percentage in percentage in gas inspired air/% expired air/% x 0.04 4.00 21.00 16.00 Zz variable saturated Identify which gas, X, Y or Z is oxygen.

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2. 0654/32 · February/March 2026 · Q2a(iii)[2]

   Calculate the percentage increase in gas X in expired air compared to inspired air. percentage increase

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3. 0654/42 · May/June 2025 · Q2c(ii)[3]

   Explain the differences in composition between inspired and expired air.

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4. 0654/43 · October/November 2022 · Q1b(i)[1]

   Use Table 1.1 to calculate the difference in percentage of oxygen between inspired and expired air. %

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5. 0654/43 · October/November 2022 · Q1b(ii)[2]

   Explain the difference in percentage of oxygen between inspired and expired air that is shown in Table 1.1.

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6. 0654/43 · October/November 2022 · Q1b(iii)[1]

   State one difference in composition between inspired and expired air that is not shown in Table 1.1.

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7. 0654/33 · May/June 2022 · Q7b[3]

   Describe how inspired air is different from expired air.

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8. 0654/11 · May/June 2021 · Q8[1]

   What is the percentage of oxygen inside the balloon?

What examiners said

Comprehensive responses • Most candidates identified oxygen from the information given in the table. Limited responses • There were insufficient incorrect responses to identify common errors.

— Examiner report, February/March 2026, 0654/32 Q2(a)(ii) (Cambridge)

Comprehensive responses • There were no correct responses to this part. Limited responses • Some candidates showed their working when attempting the calculation, even when their final answers where incorrect.

— Examiner report, February/March 2026, 0654/32 Q2(a)(iii) (Cambridge)

Candidates that recognised that the process responsible for the changes in composition was aerobic respiration, generally scored highly. Some candidates misinterpreted the question and only described the data in the table.

— Examiner report, May/June 2025, 0654/42 Q2(c)(ii) (Cambridge)