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Chemistry 5070 · Cambridge (CAIE) O Level

Percentage Composition

4 past-paper questions on Percentage Composition · examined 2022–2025.

20251 question

5070/12 · M/J · Q11 [1]Sign up to mark my answer →

The formula of hydrated sodium carbonate is Na2CO3•10H2O. What is the percentage composition by mass of oxygen in hydrated sodium carbonate?

20232 questions

5070/11 · O/N · Q10 [1]Sign up to mark my answer →

Three compounds are listed. Which row shows the element that is present in the greatest percentage by mass in each compound?

5070/12 · M/J · Q11 [1]Sign up to mark my answer →

Which compound contains 45.2% nitrogen by mass? [Ar: C, 12; H, 1; N, 14]

20221 question

5070/21 · M/J · Q9(b)(ii) [2]Sign up to mark my answer →

Calculate the percentage by mass of nitrogen in ammonium nitrate.

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