Topic: The impact of salts on the environment

Target group

Elementary school student (grades 7. and 8.)

Core curriculum:

Primary school. Chemistry.

VII. Sole. Pupil:

6) lists the application of the most important salts: chlorides, carbonates, nitrates, sulphates and phosphates (orthophosphates).

General aim of education

The student discusses the influence of salt on the natural environment

Key competences

• communication in foreign languages;

• digital competence;

• learning to learn.

Criteria for success
The student will learn:

• recognize salts found in common use and evaluate their impact on the natural environment.

Methods/techniques

• expository

  • talk.

• activating

  • discussion.

• programmed

  • with computer;

  • with e‑textbook.

• practical

  • exercices concerned.

Forms of work

• individual activity;

• activity in groups;

• collective activity.

Teaching aids

• e‑textbook;

• notebook and crayons/felt‑tip pens;

• interactive whiteboard, tablets/computers;

• sheets of gray paper;

• colored markers.

Lesson plan overview

Introduction

1. The teacher hands out Methodology Guide or green, yellow and red sheets of paper to the students to be used during the work based on a traffic light technique. He presents the aims of the lesson in the student's language on a multimedia presentation and discusses the criteria of success (aims of the lesson and success criteria can be send to students via e‑mail or posted on Facebook, so that students will be able to manage their portfolio).

2. The teacher together with the students determines the topic – based on the previously presented lesson aims – and then writes it on the interactive whiteboard/blackboard. Students write the topic in the notebook.

Realization

1. Students get acquainted with the content of the abstract and analyze subsequent points presented in the interactive illustration. Then the teacher asks the pupils to explain what is happening with the lakewhere some salts are delivered, for example from the waters washing passing fertilized fields or sewage.

2. The teacher divides the class into five teams. Each of the available sources (eg the internet, textbook or encyclopedia) prepares information on the properties and use of one of the five proposed salt groups: chlorides, nitrates, sulfates, phosphates and carbonates, indicating both advantages and harmful effects.

3. The students, working in the same groups, collected the information presented graphically on sheets of paper. After completing the activities, group leaders present team‑created infographics.

4. Students perform interactive exercises No. 1‑5. The teacher initiates a discussion during which the correct solution is discussed.

Summary

1. The teacher asks the students to finish the following sentences:

   • Today I learned ...

   • I understood that …

   • It surprised me …

   • I found out ...

   The teacher can use the interactive whiteboard in the abstract or instruct students to work with it

Homework

1. Carry out exercise number 6.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

The impact of salts on the environment

Some salts as a result of human activity are introduced into the environment, causing the imbalance. For example, substances used for the production of synthetic fertilizers and cleaning agents get into waters, causing them to degrade. Sodium chloride, which is used on roads during winter, has a negative impact on plants and soils near the road.

Rivers that carry pollutants that are nutrients for algae enter the Baltic Sea; also ships and ferries draining sewage directly into the water contribute to the intensification of the so‑called algal bloom.

• Salts occur in nature in a dissolved form in natural waters or form minerals

• Nitrates and phosphates are used, among others for the production of synthetic fertilizers.

• Calcium carbonate is, for example, a raw material for the production of building materials.

• Sodium chloride is used, among others for food, in the pharmaceutical industry and for snow‑covered streets in winter.