General Knowledge - General Science

Exercise : General Science - Synthetic Materials
21.
The type of glass used in making lenses and prisms is
jena glass
soft glass
pyrex glass
flint glass
Answer: Option
Explanation:
No answer description is available. Let's discuss.

22.
Which one of the following is the petroleum wax?
Paraffin wax
Jonoba wax
Carnauba wax
Bees wax
Answer: Option
Explanation:
Paraffin wax is obtained from petroleum by dewaxing light lubricating oil stocks. It is used in candles, wax paper, polishes, cosmetics, and electrical insulators. It assists in extracting perfumes from flowers, forms a base for medical ointments, and supplies a waterproof coating for wood. In wood and paper matches, it helps to ignite the matchstick by supplying an easily vaporized hydrocarbon fuel.