Topic: Hydrogen

Target group

Elementary school student (grades 7. and 8.)

Core curriculum:

Elementary school. Chemistry.

IV. Oxygen, hydrogen and their chemical compounds. Air. Pupil:

7) designs and conducts an experiment consisting in obtaining hydrogen and examines selected physical and chemical properties; reads from various sources (eg periodic table of the elements, solubility plot) information about this element; lists its uses; writes the hydrogen reaction equations and the hydrogen and non‑methane reaction equations; describes the physical properties and applications of selected hydrides of non‑metals (ammonia, hydrogen chloride, hydrogen sulfide).

General aim of education

The student discusses the physical and chemical properties of hydrogen

Key competences

• communication in the mother tongue;

• communication in foreign languages;

• mathematical competence and basic competences in science and technology;

• digital competence;

• learning to learn.

Criteria for success
The student will learn:

• to describe the structure of the hydrogen atom and discuss the properties of this element;

• to plan methods for obtaining and identifying hydrogen;

• to define the concept of an explosive mixture and apply in practice safety rules in a chemical laboratory;

• to analyze the properties and use of hydrogen.

Methods/techniques

• activating

  • discussion.

• expository

  • talk.

• exposing

  • film.

• 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;

• projector;

• interactive whiteboard, tablets/computers;

• methodician or green, yellow and red cards;

• equipment, laboratory glass and reagents for the experiment.

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.

3. Health and safety – before starting the experiments, students familiarise themselves with the safety data sheets of the substances that will be used during the lesson. The teacher points out the need to be careful when working with them.

Realization

1. The teacher encourages students to discuss the existence of hydrogen in nature. Then it presents an illustration with the periodic table of elements (abstract, e‑textbook, chemical table) and asks students to discuss the structure of the hydrogen atom (a reminder of the periodic table of the elements).

2. The students work independently, learning the text in the drop‑down table, and then drawing from it, describe the properties of hydrogen.

3. The lecturer conducts - in the form of a teacher's show - an experiment „Testing the properties of hydrogen”. Students formulate a research question and hypothesis, observe changes during the experiment and write everything in notebooks. After the show, they formulate conclusions. The teacher summarizes the course of the experiment. Students can also do the experiment as instructed in the abstract under the supervision of the teacher.

4. The instructor divides the students into groups. He refers them to the abstract, asking them to become familiar with the use of hydrogen, and then asks them to present the information they have acquired using the mental map method (mind map).

5. The teacher informs students that hydrogen in the synthesis reaction with other non‑metals forms chemical compounds: hydrogen chloride, hydrogen sulphide, ammonia. Writes the equation of reaction on the board (does not discuss the properties and applications of these relationships, because they will be topics of other activities).

6. The teacher teaches students to perform tasks and interactive exercises in an abstract.

7. As a homework, the teacher can suggest commands from the abstract, preferably to choose from, for example two commands.

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. Listen to the abstract recording at home. Pay attention to pronunciation, accent and intonation. Learn to pronounce the words learned during the lesson.

2. Make at home a note from the lesson using the sketchnoting method.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

Hydrogen

Hydrogen is the most widespread element in the universe – it is the main component of stars. On Earth, it occurs in trace amounts, in natural and volcanic gas, however it forms numerous compounds, e.g. water, proteins, hydrocarbons, sugars.

Hydrogen is the element that was recorded in the periodic table as first element but it does not belong to any group. It has the smallest atomic mass, due to which it is the lightest substance in the world in all states of matter *(as gas 0.00009 g/cmIndeks górny 3³, as liquid 0.07 g/cmIndeks górny 3³ and as solid 0.08 g/cmIndeks górny 3³ – its density in each of the states of matter is the smallest in comparison with other substances). Hydrogen forms diatomic molecules.

Hydrogen is a combustible gas. Pure hydrogen combusts peacefully. The ignited fire torch inserted into the test tube with pure gas formed as a result of the reaction combusts peacefully. Hydrogen mixed with a small amount of air combusts with a characteristic sound.

$\text{Zn + 2HCl → Zn}{\text{Cl}}_{\text{2}}\text{+}{\text{H}}_{\text{2}}\text{↑}$

$\text{zinc + hydrochloric acid → zinc chloride + hydrogen}$

$\text{2}{\text{H}}_{\text{2}}\text{O → 2}{\text{H}}_{\text{2}}\text{ +}{\text{ O}}_{\text{2}}$

$\text{water → hydrogen + oxygen}$

Hydrogen is a colourless, odourless gas, slightly soluble in water, it is the element with the lowest density, about 14 times lighter than air. It is a combustible gas – in pure form it combusts with a pale blue flame but does not support combustion. The mixture of hydrogen and oxygen under the influence of heating or sparks combusts violently – it is oxyhydrogen, formerly called Knallgas.

Hydrogen is a raw material for the synthesis of ammonia used in the industry for the production of artificial fertilizers. As a coolant, it is used for freezing food products. Formerly it was also used to prepare artificial ice rinks.

Hydrogen is used in hydrogen‑oxygen burners for precise metal cutting and welding, among others by jewellers. In the food industry, it is used in the margarine production process, and in the pharmaceutical industry – for the production of medicines.

Currently, a special type of battery is often used, called a fuel cell (which converts chemical energy into electricity). Liquid hydrogen is also used as a fuel for space shuttles.

• Hydrogen is the most widespread element in the universe. It creates diatomic molecules in the free state.

• Pure hydrogen combusts but it does not support combustion. It is a colourless, odourless gas of the lowest density, about 14 times lighter than air. With oxygen, it forms an explosive mixture.

• It is used for the production of ammonia, hydrochloric acid and margarine and as an ecological fuel.

Hydrogen, the lightest gas, diatomic molecule, oxyhydrogen