Q-2
Explain the difference on the basis of properties
(1) Thermosetting plastics and thermoplastics.
(2) Physical properties of metals and non metal physical properties.
(3) Useful micro organisms and harmful micro organisms.
Answers
Answer:
Explanation:
1)Thermoplastics Thermosetting plastics
Plastics which can be easily deformed and bend easily on heating are known as thermoplastics. Plastics once moulded cannot be bent or deformed are known as thermosetting plastics.
They are used for making toys, containers. They are used for making switches, handles of utensils,
Examples are PVC, Polythene Examples are Bakelite, Melamine.////
2)Some physical properties of metals are listed below.
Shiny (lustrous) in nature
Metal is a good conductor of electricity and heat
Density and melting point is high
Mouldable (Malleable)
Ductile
At room temperature, it is in solid form except for mercury
Opaque
Chemical Properties of Metals
Some chemical properties of metals are listed below.
Easily corrodible
Can lose electrons
Form basic oxides
Have low electron ome chemical properties of non-metals are listed below.
The number of electrons in the outer shell is generally 4-8
Easily gain or lose valence electrons
Form acidic oxides whenever they come in contact with oxygen
High electronegative elements
Great oxidizing agents
Properties of Non-Metals
Physical Properties of Non-metals
Some physical properties of non-metals are listed below.
Poor conductors of electricity and heat
Non-Ductile metals
Brittle solids
Maybe solids, liquids or gases at room temperature
These are not sonorous
Transparent
3)These form a significant part of the ecosystem and participate in the production of minerals and gases like oxygen, carbon dioxide.
They also feed on the dead and decaying matter by converting the complex compounds into the simpler ones.
The bio-geochemical cycle, such as the nitrogen cycle is an important example of useful microorganisms.
Microorganisms are used in various industries for the production of various metabolites such as ethanol, riboflavin, lactic acid, and butanol.
Harmful Microorganisms
There are a number of microorganisms that are responsible for food spoilage, diseases and infections. Such microorganisms are known as harmful microorganisms.
Bacteria are the most dangerous of all microorganisms and are responsible for several infectious diseases such as tuberculosis, cholera, diptheria, etc. Viruses are also responsible for certain fatal diseases such as AIDS, influenza, etc. Fungi are also harmful and can lead to certain skin infections and allergies