Metals/Non-metals

Habari Mwanafunzi! Welcome to the World of Materials!

Look around you right now. What do you see? A wooden desk? A metal window frame? The plastic case of your pen? Everything, and I mean everything, is made of different materials. Today, we are going to be detectives and classify these materials into two big, important families: Metals and Non-metals. Think of it like sorting players into two teams for a game of football. Each team has its own special skills and characteristics. Let's get started!

Image Suggestion: A vibrant, sunlit classroom in Kenya. A student is looking curiously at various objects: a metal spoon, a plastic ruler, a wooden desk, and a clay pot on a shelf. The style should be colourful and illustrative, capturing a sense of discovery.

Team 1: The Mighty Metals (The Shiny, Strong Family)

Metals are the superstars of strength and shine! We see them everywhere in Kenya, from the framework of high-rise buildings in Nairobi to the humble jembe used on the farm. They share some common family traits.

• Lustrous: This is a fancy word for shiny! When you polish a metal, it reflects light very well. Think of a brand new coin or a clean aluminium sufuria.
• Malleable: This means you can hammer a metal into thin sheets without it breaking. This is a skill our talented jua kali artisans use every day to make things like metal boxes (sandukus) and roofing sheets (mabati).
• Ductile: You can pull and stretch metals into thin wires. The copper wires that Kenya Power uses to bring electricity to our homes are a perfect example of ductility.
• Good Conductors: Metals are excellent at allowing heat and electricity to pass through them. This is why a cooking pot is made of metal (to heat the food) but the handle might be plastic (to protect your hand).
• Sonorous: When you strike a metal, it makes a ringing sound. Think of a school bell or the sound of hitting a metal gate.
• Strong and Tough: Metals can withstand heavy loads, which is why they are used to build bridges, cars, and railways.

Real-World Example: Imagine a blacksmith in a jua kali workshop. He takes a dull, red-hot piece of iron. With a loud clang, he hammers it again and again. It doesn't shatter; instead, it flattens and takes a new shape – perhaps a panga or a gate hinge. He is using the property of malleability. When it cools, it is incredibly strong and will last for years.

Team 2: The Versatile Non-Metals (The Colourful, Diverse Family)

If metals are one big, strong family, then non-metals are a diverse group of cousins with all sorts of different talents! They are just as important in our daily lives. They are often, but not always, the opposite of metals.

• Dull: Most non-metals are not shiny. Think of a piece of charcoal (makaa) or the sulphur powder you might see in the lab.
• Brittle: If you try to hammer a non-metal like sulphur or charcoal, it will shatter into many small pieces. It is not malleable.
• Poor Conductors (Insulators): They do not let heat or electricity pass through them easily. This is a very useful property! It's why electrical wires are coated in plastic and why we use a wooden spoon (mwiko) to stir hot ugali.
• Not Sonorous: Hitting a piece of wood or plastic makes a dull "thud," not a ring.
• Can be Solid, Liquid, or Gas: Unlike metals which are mostly solid, non-metals can be found in all states. Carbon (in a pencil) is solid, Bromine is a liquid, and Oxygen (the air we breathe) is a gas!

Image Suggestion: A split-scene image. On the left, a close-up of shiny, new mabati sheets stacked together, reflecting the sun. On the right, a colourful pile of different plastic basins (blue, red, green) and a dark, textured pile of charcoal.

Metals vs. Non-Metals: The Showdown!

Let's put our two teams side-by-side to see their differences clearly.

+---------------------------+--------------------------------+
|       PROPERTY            |         METALS                 |
+---------------------------+--------------------------------+
| Appearance                | Shiny (Lustrous)               |
| Response to Hammering     | Flattens (Malleable)           |
| Heat/Electricity Flow     | Good Conductor                 |
| Sound when Struck         | Ringing Sound (Sonorous)       |
| State at Room Temp.       | Mostly Solid                   |
| Example in your Home      | Sufuria, Spoon, Gate           |
+---------------------------+--------------------------------+
|       NON-METALS          |
+---------------------------+
| Dull                      |
| Shatters (Brittle)        |
| Poor Conductor (Insulator)|
| Dull Sound                |
| Solid, Liquid, or Gas     |
| Plastic basin, Charcoal   |
+---------------------------+

A Little Math: Why is Metal So Heavy?

Have you ever noticed that a small metal coin feels heavier than a larger piece of plastic? This is because of a property called Density. Density is how much "stuff" (mass) is packed into a certain amount of space (volume). Metals pack a lot of stuff into a small space!

We can calculate it using a simple formula:

Density = Mass / Volume

Let's do a quick calculation:

Imagine we have a small cube of Iron (Metal) and a cube of the exact same size of Wood (Non-metal). Let's say each cube has a volume of 10 cm³.

1. We weigh the iron cube, and its mass is 78 grams.
2. We weigh the wood cube, and its mass is only 7 grams.

Now, let's find their densities:

Iron Density = 78 g / 10 cm³ = 7.8 g/cm³

Wood Density = 7 g / 10 cm³  = 0.7 g/cm³

See? The number for iron's density is much bigger! This shows that iron is much denser than wood, which is why it feels heavier for its size.

Your Turn: Be a Material Scientist!

Now you have the knowledge to be a material detective. Your mission, should you choose to accept it, is this:

Activity: Walk around your classroom or home. Find three items made of metal and three items made of a non-metal. Create a simple table in your notebook. For each item, name it and write down one property that makes it perfect for its job.

Example:

• Item: Electrical Wire
• Material: Copper (Metal) core, Plastic (Non-metal) coating.
• Reason: Copper is ductile to be made into a wire and a good conductor to carry electricity. The plastic is an insulator to keep us safe from shock!

Fantastic work today! By understanding metals and non-metals, you've taken your first step into the amazing world of engineering and design. Keep observing, keep questioning, and keep learning!

Habari Mwanafunzi! Welcome, Future Technician!

Look around you right now. What do you see? A desk, a window, a pen, maybe a sufuria in the kitchen? Everything, and I mean everything, is made of different materials. Today, we are going to become Material Detectives! Our mission is to investigate two of the biggest families of materials in the world: Metals and Non-metals. By the end of this lesson, you will be able to look at an object and confidently say, "Aha! I know your family secrets!"

Image Suggestion: A vibrant, colourful digital illustration of a Kenyan classroom. A student is looking around with a curious expression, and various objects are highlighted with glowing outlines: a metal window frame, a plastic chair, a wooden desk, a mabati roof visible through the window. The style should be modern and engaging for a young audience.

The Shiny, Strong Family: What are Metals?

Metals are materials that are usually strong, shiny, and hard. They are the backbone of our country's development! Think about the things we use every single day.

• Mabati Roofs: The iron sheets that protect our homes from the sun and rain are a perfect example of a metal.
• Sufurias & Cooking Pots: Made from aluminium, a lightweight metal that heats up quickly to cook our ugali and sukuma wiki.
• Construction Steel: The strong steel bars used to build our schools, hospitals, and high-rise buildings in Nairobi.
• Window Frames: Many modern windows use strong frames made of steel or aluminium.
• Our Shilling Coins: That shiny one-bob coin in your pocket is made of steel coated with another metal called nickel!

The Superpowers of Metals (Their Properties)

Metals have special characteristics, or "superpowers," that make them so useful. Let's uncover them!

• Lustre: This is a fancy word for shiny! When you polish a metal, like a new sufuria, it shines brightly.
• Malleability: This means you can hammer a metal into thin sheets without it breaking. A fundi (artisan) uses this property to shape a flat piece of metal into a strong box or to make mabati sheets.
• Ductility: This means a metal can be pulled and stretched into a thin wire. Think of the copper or aluminium wires KPLC uses to bring electricity to our homes.
• Good Conductors: Metals are excellent at letting heat and electricity pass through them. That's why the whole sufuria gets hot when you put it on a jiko (good conductor of heat) and why electric wires are made of metal (good conductor of electricity).
• Sonorous: When you strike a metal, it makes a deep ringing sound. Think of the sound a school bell makes! That's a sonorous sound.

A Fundi's Choice: Imagine a fundi named Juma who needs to make a new gate for a home. He needs a material that is strong, can be shaped into bars (ductile), and can be welded together. He chooses steel, a metal, because it has all these superpowers! He wouldn't use wood, because it's not as strong and can be eaten by termites.

The Diverse Family: What are Non-Metals?

Non-metals are the opposite of metals in many ways. They come in all forms - solids, liquids, and gases! They are just as important in our daily lives.

• Charcoal (Makaa): This solid fuel we use for cooking is a form of Carbon, a very important non-metal.
• Plastics: Look at your school chair, a water bottle, or a jerrycan. These are all made from plastic, which is a non-metal product.
• Wood: Our desks, doors, and furniture are often made of wood, which is a non-metal.
• Glass: The glass in our windows is made from sand (silicon dioxide), another non-metal.
• Air: The very air we breathe is a mix of non-metal gases like Nitrogen and Oxygen!

Image Suggestion: A detailed illustration of a typical Kenyan homestead kitchen area. In the foreground, there's a person using a plastic basin to wash vegetables, a wooden cooking stick (mwiko) resting on a clay pot, and a plastic jerrycan for water nearby. In the background, a charcoal jiko is visible. This highlights the everyday use of non-metals.

The Unique Talents of Non-Metals

Non-metals have their own set of useful talents that are often the opposite of metals.

• Dull: They are not shiny. A piece of wood or charcoal does not reflect light like a metal does.
• Brittle: If you hit a solid non-metal with a hammer, it will likely shatter or break. You cannot hammer charcoal into a sheet; it will just become powder!
• Poor Conductors (Insulators): They are very bad at letting heat and electricity pass through. This is a very useful talent! The plastic handle on a sufuria is an insulator, which stops your hand from getting burned. The plastic coating on electric wires is an insulator that keeps you safe from electric shock.

Showdown: Metal vs. Non-metal

Let's put their properties side-by-side in a table to see the difference clearly.

+----------------------+-----------------------------+-----------------------------+
|      Property        |           METALS            |         NON-METALS          |
+----------------------+-----------------------------+-----------------------------+
| Appearance           | Shiny (Lustrous)            | Dull (Not shiny)            |
| Strength             | Strong, Hard                | Often Brittle (if solid)    |
| Shape Change         | Malleable & Ductile         | Not Malleable or Ductile    |
| Heat Conduction      | Good Conductor              | Poor Conductor (Insulator)  |
| Electricity          | Good Conductor              | Poor Conductor (Insulator)  |
| Sound when Hit       | Ringing Sound (Sonorous)    | Dull Sound                  |
+----------------------+-----------------------------+-----------------------------+

A Little Bit of Math: Calculating Density

One way we can tell materials apart is by their density. Density is a measure of how much "stuff" (mass) is packed into a certain amount of space (volume). It’s why a small piece of metal feels much heavier than a big piece of wood.

The formula is simple:

Density = Mass / Volume

Let's try an example. Imagine you have a small block of aluminium with a mass of 54 grams and a volume of 20 cubic centimetres (cm³). Let's find its density!

Step 1: Write down the formula.
   Density = Mass / Volume

Step 2: Put in the numbers we know.
   Density = 54 g / 20 cm³

Step 3: Do the calculation.
   54 divided by 20 = 2.7

Step 4: Write the final answer with the correct units.
   The density of the aluminium block is 2.7 g/cm³.

Think Like an Engineer!

You have learned so much! Now it's time to use your knowledge. Imagine you are designing a brand new electric kettle.

• Which material would you use for the part that actually heats the water? Why?
• Which material would you use for the handle and the outer body? Why?

Think about the properties we discussed. You need a good conductor of heat for one part and a good insulator for the other to keep the user safe. Sawa?

Fantastic Work, Detective!

Well done! You have successfully investigated the families of metals and non-metals. You are no longer just a student; you are a materials scientist in the making!

Remember these key points:

• Metals are typically shiny, strong, malleable, ductile, and good conductors of heat and electricity.
• Non-metals are typically dull, brittle, and poor conductors (insulators).
• Every material is chosen for a job based on its unique properties or "superpowers".

Keep your eyes open and continue to observe the amazing world of materials all around you!

Habari Mwanafunzi! Welcome to the World of Materials!

Look around you right now. What do you see? Your desk, a pen, the window frame, your school bag, and maybe even the boda boda passing by outside. Everything you see is made of different 'stuff'. In Pre-Technical studies, we call this 'stuff' materials. Today, we are going to explore the two biggest families in the world of materials: Metals and Non-metals. Are you ready? Let's begin our adventure!

Meet the Metals! (Chuma na Nguvu Zake)

Metals are a group of materials that are strong, shiny, and have some very special abilities. Think about the things a jua kali artisan uses to make strong gates, durable sufurias, or even the frame of a bicycle. They are all made of metals!

Image Suggestion: A vibrant, sunlit outdoor 'jua kali' workshop in Kenya. A male artisan is skillfully welding a metal window frame, with sparks flying. In the background, there are various metal objects: corrugated iron sheets (mabati), steel rods, and a finished metal gate. The scene should be full of energy and craftsmanship.

Here are the common properties (or characteristics) of metals:

• Lustrous: This is a fancy word for shiny! When you polish a metal, like a new aluminium sufuria, it reflects light very well.
• Malleable: This means you can hammer or press a metal into different shapes without breaking it. Think of a fundi (craftsman) hammering a flat piece of metal into the shape of a box.
• Ductile: Metals can be pulled and stretched into thin wires. The copper wires that KPLC uses to bring electricity to our homes are a perfect example!
• Good Conductors: Metals are excellent at allowing heat and electricity to pass through them. This is why your mum's cooking pot is made of metal (to heat the food) but has a plastic or wooden handle (which is a non-metal and a poor conductor).
• Sonorous: When you hit a metal, it makes a ringing sound. Your school bell is a great example of a sonorous material!
• High Density: Generally, metals are heavy for their size. If you have a small piece of iron (like a bolt) and a piece of wood of the same size, the iron will feel much heavier.

Exploring the Non-Metals (Vitu Visivyo vya Chuma)

Non-metals are the opposite of metals in many ways. They are just as important and are all around us. The air we breathe (Oxygen, Nitrogen), the charcoal for the jiko, the plastic chair you sit on, and the wood for your desk are all non-metals!

Real-World Scenario: Ever wondered why we use a wooden spoon (mwiko) to stir hot ugali or stew in a metal sufuria? It's because wood is a non-metal and a poor conductor of heat (an insulator). If you used a metal spoon, the handle would get very hot and burn your hand! This shows how we use the properties of materials every day.

Here are the common properties of non-metals:

• Dull: They are not shiny. A piece of charcoal or a plastic ruler does not reflect light like a metal does.
• Brittle: When you try to hammer or bend a solid non-metal, it usually breaks or shatters. Try bending a piece of charcoal - it will just snap!
• Non-Ductile: You cannot make wires out of non-metals.
• Poor Conductors (Insulators): They do not let heat or electricity pass through easily. This is why electrical wires are covered in plastic or rubber – to protect us from electric shock.
• Low Density: They are generally light for their size. Think of a plastic basin versus a metal one of the same size.

Let's Do Some Quick Math! Understanding Density

Density helps us understand why a small piece of metal feels heavier than a large piece of plastic. The formula is simple:

Density = Mass / Volume

Imagine we have a small block of Aluminium (a metal) and a block of Wood (a non-metal). Both blocks are the exact same size, let's say 10 cubic centimetres (cm³) in volume.

• The mass of the Aluminium block is 27 grams.
• The mass of the Wood block is only 7 grams.

Let's calculate their densities!

### Calculation for Aluminium (Metal) ###

Density = Mass / Volume
Density = 27 g / 10 cm³
Density = 2.7 g/cm³

### Calculation for Wood (Non-metal) ###

Density = Mass / Volume
Density = 7 g / 10 cm³
Density = 0.7 g/cm³

You see? The metal has a much higher density! It packs more 'stuff' (mass) into the same amount of space.

A Quick Guide: Metal or Non-Metal?

Here is a simple flowchart to help you identify a material. Think of it like a detective's guide!

Start Here: You have an unknown object.
     |
     V
Is it shiny (lustrous)?
     |
     +---- [YES] ---> Does it feel heavy for its size?
     |                  |
     |                  +--- [YES] ---> It is very likely a METAL!
     |                  |
     |                  +--- [NO] ----> Could be a light metal like Aluminium.
     |
     +---- [NO] ----> Is it dull?
                        |
                        +--- [YES] ---> Try to tap it. Does it break easily (brittle)?
                                       |
                                       +-- [YES] --> It is very likely a NON-METAL!

Image Suggestion: A close-up, split-screen style photo. On the left, a polished, shiny metallic silver spanner reflecting light. On the right, a piece of dark, matte charcoal with a rough texture. The contrast should clearly illustrate the concept of 'Lustrous vs. Dull'.

Summary: The Big Showdown!

Let's put everything side-by-side in a simple table to help you remember.

+----------------------+-----------------------------+--------------------------------+
|       Property       |           METALS            |           NON-METALS           |
+----------------------+-----------------------------+--------------------------------+
| Appearance           | Shiny (Lustrous)            | Dull (Not shiny)               |
| Response to Hammering| Malleable (Bends)           | Brittle (Breaks)               |
| Can it be a wire?    | Yes (Ductile)               | No (Non-ductile)               |
| Conducts Heat?       | Yes (Good Conductor)        | No (Poor Conductor/Insulator)  |
| Conducts Electricity?| Yes (Good Conductor)        | No (Poor Conductor/Insulator)  |
| Sound when hit       | Ringing sound (Sonorous)    | Dull thud                      |
| Density              | High (Usually heavy)        | Low (Usually light)            |
| Example in Kenya     | Jembe, Sufuria, Mabati      | Charcoal, Plastic chair, Mwiko |
+----------------------+-----------------------------+--------------------------------+

Your Turn, Future Technician!

Amazing work today! You have learned the fundamental differences between metals and non-metals. This knowledge is the foundation for choosing the right materials for any job, whether you become an engineer, a builder, or a top artisan.

Activity: Walk around your classroom or home. Find and list three objects made of metal and three objects made of a non-metal. For each object, write down one property you observed that helped you decide. For example: "Sufuria - Metal because it is shiny and conducts heat."

Keep exploring and stay curious!