Lesson Notes By Weeks and Term - Senior Secondary 3

TERM׃ I^ST TERM

WEEK THREE

Class: Senior Secondary School 3

Age: 17 years

Duration: 40 minutes of 5 periods each

Date:

Subject: Chemistry

Topic: Metals and their Compounds 3

SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to

1. Explains the general properties of transition metals
2. List the 1^st transition series and explain their electronic configuration.
3. Discuss the extraction and uses of Tin.

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers,

demonstration, videos from source

INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

NOTE

METALS AND THEIR COMPOUNDS 3

Extraction of Tin

Tin is commonly extracted from its ore, cassiterite (SnO₂). The extraction process involves several steps as follows,

1. Mining: Cassiterite is mined from deposits in the Earth's crust.
2. Concentration: The ore is crushed and ground to concentrate the tin-bearing minerals.
3. Gravity Separation: Heavy particles, including cassiterite, are separated from lighter minerals using gravity.
4. Smelting: The concentrated ore is heated with carbon in a furnace to reduce the tin oxide to metallic tin. This process typically produces crude tin, which may contain impurities.
5. Refining: The crude tin is further processed to remove impurities through refining methods such as liquation or electrolysis.
6. Casting: The refined tin can be cast into various shapes like ingots for commercial use.

Uses of Tin

Tin has various applications across different industries. Some notable uses include:

1. Tin is a key component of solder, a material used for joining electronic components in electrical circuits.
2. Tin is often used as a coating for steel to create tinplate, which is widely used for food and beverage packaging.
3. Tin is alloyed with other metals to create alloys with desirable properties. For example, bronze, which is a tin-copper alloy, is known for its strength and corrosion resistance.
4. Tin is used to coat other metals, such as in the production of tin cans to prevent corrosion.
5. Tin compounds are utilized in various chemical applications, such as catalysts and stabilizers.
6. Some tin compounds exhibit superconducting properties, making them valuable in certain applications within the field of superconductivity.

Transition Metals

Transition metals are a group of elements in the periodic table that are characterized by the presence of partially filled d orbitals in their atomic structure. The first series of transition metals includes elements from Scandium (Sc) to Zinc (Zn), spanning the 3d block of the periodic table.

Below is the electronic configuration of transition metals.

 The following are some general properties of transition metals in this series:

1. Variable Oxidation States: Transition metals in the first series commonly exhibit multiple oxidation states due to the availability of electrons in their d orbitals. For example, iron (Fe) can have oxidation states of +2 or +3.
2. Formation of Complex Ions: Transition metals readily form complex ions or coordination compounds by interacting with ligands. This ability is attributed to the presence of accessible d orbitals.
3. Colored Compounds: Many transition metal compounds exhibit vibrant colors due to the absorption of specific wavelengths of light associated with electronic transitions in the d orbitals.
4. High Melting and Boiling Points: Transition metals generally have higher melting and boiling points compared to main group elements, reflecting strong metallic bonding.
5. Magnetic Properties: Some transition metals and their compounds are magnetic, displaying paramagnetic or ferromagnetic behavior due to unpaired electrons in the d orbitals.
6. Catalytic Activity: Transition metals often serve as catalysts in various chemical reactions, taking part in redox processes and facilitating reaction pathways.
7. Density: Transition metals tend to have higher densities compared to other elements, reflecting their relatively large atomic masses.
8. Malleability and Ductility: Transition metals are typically malleable and ductile, allowing them to be hammered or drawn into thin wires.

EVALUATION:   1. Discuss the extraction of Tin

2. Write down four uses of Tin.
3. What are transition metals?
4. Write down the electronic configuration of Scandium and titanium.

CLASSWORK: As in evaluation

CONCLUSION: The teacher commends the students positively