Non-Metals
As opposed to metals, non-metallic elements are very brittle and cannot be rolled into wires or pounded into sheets.Non-metals have low melting and boiling points. This note describes features of non-metals and its uses.
Summary
As opposed to metals, non-metallic elements are very brittle and cannot be rolled into wires or pounded into sheets.Non-metals have low melting and boiling points. This note describes features of non-metals and its uses.
Things to Remember
- Non-metals are the elements in groups 14-16 of the periodic table.
- Non-metals are a bad conductor of electricity or heat.
- Silicon is not found in a pure state. Silicon is the most abundant electropositive element in The Earth’s crust.
- Sulphur is a chemical element with symbol S and atomic number 16.
- Dolomite and Gypsum are the ores of sulphur.
- Silica and Feldspar are the ores of silicon.
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Non-Metals
Non-metals are the elements in groups 14-16 of the periodic table. Non-metals are the bad conductor of electricity or heat. As opposed to metals, non-metallic elements are very brittle and cannot be rolled into wires or pounded into sheets. Non-metals have low melting and boiling points.
Silicon
Silicon is not found in the pure state. Silicon is the most abundant electropositive element in the earth’s crust. It’s a metalloid with a marked metallic lustre and very brittle. Some important ores of silicon are:
- Silica
- Feldspar
- Kaolinite
- Mica
Source: www.thinglink.com
Fig: Silicon
Properties
- It is grey solid non-metal.
- It is found in both crystalline and amorphous formed.
- It is a weak electrolyte in crystalline form but strong electrolyte in amorphous form.
- It doesn't react with air, water and acid.
- It is used to make glasses.
- It is used to make the clay pot.
- It is used to make statue and buildings.
- Silicon chip is used to make semiconductors.
- It is used to make polish and paints.
Sulphur
Sulphur is a chemical element with symbol S and atomic number 16. It is an abundant, multivalent non-metal. Some important ores of sulphur are:
- Dolomite
- Gypsum
- Calcite
- Quartz
- Pyrite
Source: www.pbase.com
Fig: Sulphur
- Sulphur is found in both crystalline and amorphous form.
- It is not soluble in water.
- It is the bad conductor of heat and electricity.
- Sulphur dioxide is formed when sulphur is burnt in the presence of air.
- It doesn't react easily with acid.
- Milk of sulphur is used in medicine.
- Sulphur is used in the manufacture of matches, gunpowder etc.
- It is also used as disinfectant.
- It is also used in the vulcanization of rubber.
Lesson
Metals and Non-Metals
Subject
Science
Grade
Grade 8
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