Chemistry
Answer
Duralumin is used rather than pure aluminium in construction work due to the following reasons:
- Duralumin is light and strong, while aluminium is light and weak. It is also unaffected by moist air. Duralumin has a strength up to six times greater than pure aluminium.
- It is corrosion-resistant and has high tensile strength.
Related Questions
Name the alloy used for the following purposes.
(a) Making electric circuits
(b) Making medals
(c) Making parts of watches
(d) Surgical instruments
(e) Aircraft
A fuse wire is an alloy made of tin and lead. It is a safety device that prevents the damage of electronic gadgets due to excessive flow of current. Can copper replace tin when making alloys? Justify your answer.
Using the information in the table below, complete the following :
(i) …………… is the metallic element.
(ii) Metal atoms tend to have a maximum of …………… electrons in the outermost energy level.
(iii) Non-metallic elements tend to form …………… oxides while metals tend to form …………… oxides.
(iv) Non-metallic elements tend to be …………… conductors of heat and electricity.
(v) Metals tend to …………… electrons and act as …………… agents in their reactions with elements and compounds.
X Y Normal electronic configuration 2, 8, 7 2, 8, 2 Nature of oxide Dissolves in water and turns blue litmus red Very low solubility in water. Dissolves in hydrochloric acid Tendency for oxidizing and reducing reactions Tends to oxidise elements and compounds Tends to act as a reducing agent Electrical and thermal conductivity Very poor electrical conductor and poor thermal conductivity Good electrical conductor and good thermal conductor Tendency to form alloys and amalgams No tendency to form alloys Forms alloys The main ore used for the extraction of iron is:
- Haematite
- Calamine
- Bauxite
- Cryolite