Year 1 chemistry at technical school: Scienze sperimentali

Mid-September 2026: in the first-year classes of the technological sector of Italian technical institutes (secondary schools with a vocational and technical focus), the teacher has just started (or is about to start) chemistry — matter and energy, states of matter, then the atom and the periodic table. The first test arrives in five to eight weeks, so between the end of October and mid-November. But this year, for the first time, you may not find a separate “Chemistry” line on the register or the school report: you find Scienze sperimentali (experimental sciences), with a single grade. It is not a mistake by the school: it is a real regulatory change, and it is worth understanding before you worry about a grade that looks “strange”.

What changes (and what doesn’t) with Scienze sperimentali

From 2026/27, for first-year classes of technical institutes only, the new regulations of Ministerial Decree 29 of 19 February 2026 come into force: they roll out one year at a time, so for now they only concern Year 1. Classes from Year 2 to Year 5 stay on the old regulations (DPR 88/2010), the one with Physics and Chemistry as separate subjects, each with its own grade.

For Year 1, instead, Physics, Chemistry, Biology and Earth Sciences merge into a single subject, Scienze sperimentali, with a single grade on the report. The content is the same as ever — in the first term, mostly chemistry — but it is decided by the individual school’s programme, so it can vary slightly from one institute to another. If you have an older brother or sister already at technical school, their booklet with “Chemistry” on its own is no longer the reference for someone entering Year 1 this year: they are two different grading systems, in two different years of the same school.

What does not change is what you really study in these weeks. Anyone writing to me because they “no longer understand what chemistry is in the programme” actually has exactly the same topic in front of them as someone who started Year 1 a year ago: only the name on the report is different.

Another useful clarification, because it causes confusion between families from different types of school: this applies to the technological sector (mechanics and mechatronics, electronics and electrical engineering, information technology and telecommunications, materials chemistry, CAT, agriculture, and the other science-based technical tracks). In the economic sector (AFM, RIM, SIA, Tourism) Year 1 has Physics, not Chemistry — Chemistry arrives there in Year 2. If you are not sure which sector your school is in, the timetable in the school’s three-year educational plan (the PTOF) clarifies it in a minute.

What the test really asks at this point

The September-October block covers, in order: matter and energy, states of aggregation and changes of state, mixtures and pure substances, then the first elements of atomic structure and the periodic table, and finally the types of chemical bond. The end-of-October test almost always asks you to:

1. correctly calculate and convert density and other basic physical quantities;
2. tell a mixture from a pure substance, and a homogeneous mixture from a heterogeneous one;
3. describe the structure of the atom (protons, neutrons, electrons, atomic number and mass number) and place it in the periodic table;
4. recognise, at a qualitative level, the type of bond between two elements.

Later in the year, in spring, you will also get the balancing of the first chemical reactions and the first calculations with moles — an important head start, because in other tracks these topics mainly appear from the second or third year. It is worth knowing this from now: anyone who arrives in good shape on the atom and the periodic table starts ahead when, in a few months, the course moves on to balancing.

The mistakes that cost marks

• Mixing up units of measurement in density. $1{\text{g/cm}}^3=1000{\text{kg/m}}^3$: forgetting the factor 1000 when moving between the two units is the most frequent mistake in the first test of the year.
• Swapping atomic number and mass number. The atomic number $Z$ counts the protons (it identifies the element); the mass number $A$ counts protons plus neutrons. Using $A$ instead of $Z$ to count the electrons of a neutral atom leads to a chain of errors across the whole exercise.
• Forgetting isotopes in the calculation of atomic mass. The atomic mass you read in the periodic table is a weighted average over the abundances of the natural isotopes, not the mass of a single “typical” atom.
• Classifying a mixture wrongly. Air and sea water are homogeneous mixtures (only one visible phase) even though they contain several substances; wood or granite are heterogeneous mixtures (phases that can be told apart by eye or under the microscope). It is not the presence of several substances that decides, but whether they can be told apart by eye.
• Deciding the bond by looking only at the formula, not at the elements. The type of bond depends on who is bonding (a metal with a non-metal, two non-metals, two atoms of the same metal), not on the number of atoms in the formula.

The method, step by step

For density and conversions:

1. Measure or read mass and volume in the units given by the problem.
2. Apply $\rho =m/V$.
3. If you need the result in another unit, convert before comparing with a density table: $1{\text{g/cm}}^3=1000{\text{kg/m}}^3$.

To recognise mixtures and pure substances:

1. Ask yourself: can you see more than one phase (with the naked eye or under the microscope)? If so, it is a heterogeneous mixture.
2. If you see only one phase, does it contain more than one substance (even if you can’t see it)? If so, it is a homogeneous mixture (a solution); if not, it is a pure substance.
3. A pure substance is an element if it cannot be broken down into simpler substances, a compound if it can.

For the structure of the atom:

1. The atomic number $Z$ = number of protons = number of electrons in the neutral atom.
2. The mass number $A$ = protons + neutrons, so the neutrons are found with $A-Z$.
3. Isotopes of the same element have the same $Z$ but a different $A$ (a different number of neutrons).

Three worked examples

1. Density to identify a material

A test piece has a mass of $135\text{g}$ and a volume of $50{\text{cm}}^3$. What material could it be made of, knowing that aluminium has a density of $2.7{\text{g/cm}}^3$ and iron $7.9{\text{g/cm}}^3$?

The value matches the density of aluminium: the test piece is (almost certainly) aluminium, not iron. In kg/m³, for comparison with data given in SI units:

2. Homogeneous mixture, heterogeneous mixture or pure substance?

Classify: sea water, granite, distilled water, air.

• Sea water: it contains water, dissolved salts and other substances, but it appears as a single transparent liquid phase → homogeneous mixture (a solution).
• Granite: with the naked eye you can tell apart the individual crystals of different minerals → heterogeneous mixture.
• Distilled water: no other substance dissolved, it cannot be broken down into other substances by simple physical means → pure substance (a compound, ${\mathrm{H}}_2\mathrm{O}$).
• Air: nitrogen, oxygen and other gases mixed in a single gas phase, indistinguishable by eye → homogeneous mixture.

3. Isotopes and atomic mass

Chlorine ($Z=17$) exists in nature mainly as two isotopes: ${}^{35}\mathrm{Cl}$ (mass $35$, abundance $75\%$) and ${}^{37}\mathrm{Cl}$ (mass $37$, abundance $25\%$, values rounded for simplicity). Describe the structure of each isotope and calculate the average atomic mass.

For both isotopes, protons and electrons are equal to $Z=17$ (it is the same element). The neutrons are calculated from $A-Z$:

The average atomic mass is the weighted average over the abundances, not the simple average of $35$ and $37$:

This is why in the periodic table chlorine appears with an atomic mass of $35.5$ and not a whole number: no single chlorine atom really weighs 35.5, but it is what you get by averaging over many real atoms, some lighter and some heavier.

How I work on this topic in my lessons

With those starting chemistry in Year 1 at technical school I always begin by connecting the concepts to something you can touch or measure: density with real objects before formulas, mixtures with examples from home (water and oil, water and salt, air) before definitions, and only afterwards the structure of the atom, which otherwise remains an abstract drawing with nothing to hook onto. The material on my science pages follows the same path. For density, states of matter and mixtures as seen at the high school (liceo) there is Science in Year 1: density and states of matter; the next step, in Year 3, is Electron configuration and quantum numbers: the method.

To practise outside the lesson too, the site has the high-school test practice papers: for now they mainly cover maths and physics, and there is no chemistry practice test yet, but they are still useful for getting used to working against the clock. When you reach the balancing of reactions in spring, the typical mistakes (and how to avoid them) are collected in a dedicated guide: balancing chemical equations in Year 2 — it is written for Year 2 of high school, but the balancing method is identical to the one you will see.

If you want to set up the topic properly before the end-of-October test, or you already have a marked test to go through together, write to me: we can start with a single lesson or the 10-hour package — the price list is always on the pricing page — if you want to follow the whole module continuously, plus a free 30-minute introductory call if you first just want to understand how I work. Payment is always offline — bank transfer, Satispay, PayPal, card, Apple Pay or Revolut.