National 5 Chemistry: the shorter 2027 exam, the assignment and practice questions

The National 5 Chemistry exam in 2027

The exam counts for 80% and the assignment for 20%, with no scaling. These figures are in the course specification valid from session 2026 to 2027, and the date is from the 2027 timetable. Until 2026, Section 1 had 25 marks and Section 2 had 75. Qualifications Scotland cut both after a survey of learners and teachers. What you're taught hasn't changed.

The assignment: you research a topic, carry out an experiment and write a report. The whole task should take no more than 8 hours, with at most 1 hour 30 minutes to write the report under supervision. Qualifications Scotland marks it.

What National 5 Chemistry covers

• Chemical changes and structure: rates of reaction, atomic structure and bonding, formulae and reacting quantities, and acids and bases.
• Nature's chemistry: homologous series, everyday consumer products and energy from fuels.
• Chemistry in society: metals, plastics, fertilisers, nuclear chemistry and chemical analysis.

National 5 Chemistry grade boundaries

In 2026, on the old format, out of 125 (the 100-mark paper plus the assignment scaled to 25), an A needed 86, a B 73, a C 61 and a D 48. Of the 15,070 candidates, 44.0% got an A (course report 2026). The 2027 course is out of 100, so those numbers won't carry over. As a guide, the grading system aims for a C at about 50% and an A at about 70%.

National 5 Chemistry practice questions

We wrote these for this guide. Take relative atomic masses from the data booklet, and show your working.

1. Moles and mass

Question: what is the mass of 0.25 mol of calcium carbonate, CaCO₃? Answer: the gram formula mass is 40 + 12 + (3 × 16) = 100 g. Mass = moles × gram formula mass = 0.25 × 100 = 25 g. Check others with the Molar Mass Calculator.

2. Concentration

Question: how many moles of sodium hydroxide are in 50 cm³ of a 0.20 mol l⁻¹ solution? Answer: change the volume to litres: 50 cm³ = 0.050 l. Moles = concentration × volume = 0.20 × 0.050 = 0.010 mol.

3. Energy from fuels

Question: burning some ethanol raises the temperature of 200 cm³ of water by 15 °C. How much energy did the water absorb? (c = 4.18 kJ kg⁻¹ °C⁻¹, from the data booklet.) Answer: 200 cm³ of water has a mass of 0.200 kg. E_h = cmΔT = 4.18 × 0.200 × 15 = 12.5 kJ. Use the mass of the water, not of the fuel: the 2026 report found few candidates got full marks on a question like this.

4. Isotopes and relative atomic mass

Question: chlorine's relative atomic mass is 35.5. Why isn't it a whole number? Answer: chlorine is a mixture of isotopes, mainly chlorine-35 and chlorine-37. The relative atomic mass is the average mass of the atoms, taking account of how much of each isotope there is: with 75% chlorine-35, that's 0.75 × 35 + 0.25 × 37 = 35.5. Practise this in our Atomic Structure course and press Mark.

5. Formulae with Roman numerals

Question: write the formula of iron(III) oxide. Answer: the (III) gives iron a valency of 3, and oxygen's valency is 2. Swap and cancel: Fe₂O₃.

Common National 5 Chemistry mistakes

From the 2026 course report:

• Choosing a radioactive source by the radiation it gives off but ignoring its half-life. Check both.
• Energy calculations that use the wrong mass or miss a step.
• Formulae with Roman numerals, such as uranium(IV) oxide, written wrongly.
• Monomers from a repeating unit: drawing the second monomer of a copolymer.
• Graphs: losing marks for unfinished plotting when the axes and first points are given.

Use a daily paper as a short timed prelim

Today's National 5 Chemistry paper covers atomic structure and isotopes, bonding, moles and reacting masses, concentration and titration, rates of reaction, energy changes, electrolysis, organic chemistry and chemical analysis. It also includes reversible reactions and equilibrium, which aren't in National 5, and it doesn't cover plastics, fertilisers or nuclear chemistry, or have an objective test section. Use it alongside the official past papers, remembering that papers before 2027 are longer. For prelim dates, see our prelims guide.

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