Metals and non-metals class 8 | CBSE Class 8 Worksheets
Metals and non metals, science chapter 4 class 8
metals and non metals for class 8 worksheet including fill in the blanks, short and long questions on metals and nonmetals class 8 chapter 4.
Metals And Non-Metals Class 8 | CBSE Class 8 science worksheet
Metals are elements that form positive ions by losing electrons and non-metals are elements that form negative ions by gaining electrons.
Elements with 4 valence electrons are normally metalloids.
Non-Metals do not react with water and dilute acids.
Metals react with dilute hydrochloric and sulphuric acids to form the corresponding salts and to liberate hydrogen.
Corrosion is the process by which materials, such as metals are slowly eaten away when exposed to air and moisture.
An alloy is the mixture of two or more metals, or one or more metals, and a non-metal, which has properties to suit certain applications.
Download metals and non-metals pdf worksheet. including questions based on fill in blanks, complete the reaction, give reasons, and more. We have added the latest syllabus questions based on NCERT Pattern and important not only for grade 8 but till higher classes as well as for science olympiads.
You saw that the shape of the iron nail and the aluminum wire changed on beating. If they were beaten harder these could be changed into sheets. You might be familiar with silver foil used for decorating sweets. You must also be familiar with the aluminum foil used for wrapping food. The property of metals by wrapping food. The property of metals by which they can be beaten into thin sheets is called malleability.
The property of metal by which it can be drawn into wires is called ductility. Since metals produce ringing sounds, they are said to be sonorous. The materials other than metals are not sonorous. we can say that some materials are hard, lustrous, malleable, ductile, sonorous, and good conductors of heat and electricity. The materials which generally possess these properties are called metals. Examples of metals are iron, copper, aluminium, calcium, magnesium, etc.
materials like coal and sulphur are soft and dull in appearance. They break down into a powdery mass on tapping with a hammer. They are not sonorous and are poor conductors of heat and electricity. These materials are called non-metals. Examples of non-metals are sulphur, carbon, oxygen, phosphorus, etc. Metals like sodium and potassium are soft and can be cut with a knife Mercury is the only metal that is found in the liquid state at room temperature. These are exceptions.
The name of the product formed in the reaction of sulphur and oxygen is sulphur dioxide gas. When sulphur dioxide is dissolved in water sulphurous acid is formed. The reaction can be given
Sulphur dioxide (SO2) + Water (H2O) ----> Sulphurous acid (H2SO3)
Generally, non-metals do not react with water though they may be very reactive in air. Such non-metals are stored in water. For example, phosphorus is a very reactive non-metal. It catches fire if exposed to air. To prevent the contact of phosphorus with atmospheric oxygen, it is stored in water.
Metals react with sodium hydroxide to produce hydrogen gas. Reactions of non-metals with bases are complex.