Topic: The world consists of atoms

Supplementary material for use in lessons in the group of natural sciences (nature, biology, chemistry, geography, physics), additional classes, science clubs. It can serve as a resource for expanding knowledge, preparing students for science competitions.

Target group:

7th‑grade students of elementary school (chemistry).

Core curriculum

7th‑grade of elementary school - chemistry

II. Internal structure of matter. Student:

1) uses the term chemical element as a set of atoms with a given atomic number Z;

8) describes how the atom differs from the molecule; interprets entries, e.g. H₂, 2H, 2H₂.

General aim of education

The student acquires knowledge and skills about the topics discussed in the classes

Key competences

• communication in foreign languages;

• digital competence;

• learning to learn.

Criteria for success
The student will learn:

• describe the structure of matter and all the substances that make up the world around us;

• present substances as a collection of various particles;

• correctly use the terms „particle”, „atom”, „molecule”;

• depict the molecular structure of matter on the model.

Methods/techniques

• expository

  • talk.

• activating

  • discussion.

• programmed

  • with computer;

  • with e‑textbook.

• practical

  • exercices concerned.

Forms of work

• individual activity;

• activity in pairs;

• activity in groups;

• collective activity.

Teaching aids

• e‑textbook;

• notebook and crayons/felt‑tip pens;

• interactive whiteboard, tablets/computers;

• plasticine.

Lesson plan overview

Before classes

• Students get acquainted with the content of the abstract. They prepare to work on the lesson in such a way to be able to summarize the material read in their own words and solve the tasks themselves.

Introduction

• The teacher gives the topic, the goals of the lesson in a language understandable for the student, and the criteria of success.

Realization

• The teacher introduces students to the topic of the lesson, asking what is building all the elements of the world around us. Then he asks his pupils to read two fragments of the abstract: „Atoms – building blocks of the world” and „How many atoms are there?”.

• Students independently perform interactive exercise no. 1.

• The teacher presents and discusses the interactive illustration. He then divides the students into groups and recommends that each of them carry out an in‑depth analysis of one of the points presented in the diagram, based on available sources of information (e.g. internet, atlas or encyclopedia). Students present the results of work in groups. Each team ends their presentation with the wording of the conclusions.

• The teacher presents and discusses illustrations showing examples of various types of matter construction („Gallery 1”). He asks students to count how many atoms an oxygen molecule is made up of. Then the teacher gives plasticine to the students and asks on the basis of the information they have obtained to make the oxygen and water model themselves. The teacher discusses the work done.

• The students consolidate the acquired information, discussing it with their nearest neighbors („tell your neighbor” method).

• Students write from the „Glossary” to the notebook definition of an atom, molecules and particles.

Summary

• Students independently perform interactive exercise no. 2 and interactive exercise no. 3.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

The world consists of atoms

Every day we use many different materials, which gradually wear out. For example, a knife that is often used is blunted and its blade decreases over time. What happened to the rest? Has it disappeared?
Let's take a copper wire: if we cut it, we'll get filings that can be crushed even further. We will get then particles so small that they can not be seen even under a microscope. These particles are atoms or molecules.

How small are atoms? What sizes do they have?The dot at the end of the sentence in the book is made of around one hundred billion atoms in the ink. If each of them had a diameter of a millimeter, then arranged one after the other would create a line of a hundred thousand kilometers long. This line would surround the whole Earth 2.5 times!
We know a little over 100 different atoms. Atoms of one type have the same properties. A substance consisting of atoms of one kind is called a element. Copper atoms form a copper plaque, and carbon atoms - pencil graphite.
Atoms often merge into groups called molecules. This type of particles consists, for example, of water, each molecule being made up of oxygen and hydrogen atoms, or sugar, the particles of which are made up of three kinds of atoms – carbon, hydrogen and oxygen.

• All objects that surround us consist of very small, invisible elements - atoms or molecules (groups of atoms), which we call particles.

• The particles can be atoms or groups of atoms, which we call molecules.