Unit - 13 Metal and Non-Metal

Unit - 13

 Metal and Non-Metal

summary

1. Division of metals into three categories, metals, non-metals and semi-metals based on their properties

has been done

2. A metal that is hard in the solid state but can be made thin and long by beating

It is said

3. Available in solid, liquid and gaseous state but cannot be made thin and long by beating

Metal is called nonmetal.

4. Elements that have both metal and non-metal properties are called semi-metals.

5. Metals are hard, malleable and good conductors of heat and electricity.

3. Write answers to the following questions:

  (a) Into how many categories are elements generally divided?

  (b) List any four properties of metals.

  (c) List any four properties of non-metals.

  (d) any four utility articles of metal.

  (e) Any two utility articles of copper metal.

Answer 👉 

(a) Elements are generally divided into three categories: metals, non-metals, and metalloids.

(b) Four properties of metals are:

• Metals are good conductors of heat and electricity.
• Metals are malleable (they can be hammered into sheets) and ductile (they can be drawn into wire).
• Metals have a characteristic luster (shine).
• Metals are generally solids at room temperature (except for mercury, which is a liquid).

(c) Four properties of non-metals are:

• Non-metals are (usually) poor conductors of heat and electricity.
• Non-metals are not malleable or ductile.
• Non-metals do not have a characteristic luster.
• Non-metals can be solids, liquids, or gases at room temperature.

(d) Four utility articles of metal are:

• Metals are used to make buildings, bridges, and other structures.
• Metals are used to make cars, airplanes, and other vehicles.
• Metals are used to make tools and machinery.
• Metals are used to make jewelry and other decorative items.

(e) Two utility articles of copper metal are:

• Copper is used to make electrical wiring.
• Copper is used to make plumbing pipes.

4. Define the following words:

  (a) Metal

A metal is a chemical element that has a characteristic luster (shine), is malleable (can be hammered into sheets), and ductile (can be drawn into wire). Metals are good conductors of heat and electricity. They are typically solids at room temperature (except for mercury, which is a liquid).

(b) Nonmetal

A nonmetal is a chemical element that does not have a characteristic luster (shine), is not malleable or ductile, and is a poor conductor of heat and electricity. Nonmetals can be solids, liquids, or gases at room temperature.

(c) Semimetal

A semimetal is a chemical element that has properties that are intermediate between those of metals and nonmetals. Semimetals are typically semiconductors, meaning that they can conduct electricity under certain conditions.

Here are some examples of metals, nonmetals, and semimetals:

• Metals: iron, copper, gold, silver, aluminum
• Nonmetals: oxygen, nitrogen, chlorine, carbon, sulfur
• Semimetals: silicon, germanium, arsenic, antimony, tellurium