Give one word or a phrase for the statement : The substance prepared by adding other metals to a base metal in appropriate proportions to obtain certain desirable properties.
Alloy
State one relevant observation for the reaction : Sulphide ore is added to a tank containing oil and water and then stirred or agitated with air.
The ore is wetted by the oil and gets separated from the gangue in the form of froth. The impurities gets wetted by water and remain behind in the sink.…
Match the alloys given in column I with the uses given in column II
| Column I | Column II |
|---|---|
| (i) Duralumin | A: Electrical fuse |
| (ii) Solder | B: Surgical instruments |
| (iii) Brass | C: Aircraft body |
| (iv) Stainless steel | D: Decorative articles |
Column I Column II (i) Duralumin C: Aircraft body (ii) Solder A: Electrical fuse (iii) Brass D: Decorative articles (iv) Stainless steel B: Surgical instruments
Answer the following questions based on the extraction of aluminium from alumina by Hall- Heroult’s Process. (i) What is the function of cryolite used along with alumina as the electrolyte. (ii) Why is the powdered coke sprinkled on top of the electrolyte. (iii) Name the electrode from which aluminium is collected.
(i) Addition of cryolite — lowers the fusion point of the mixture i.e., mixture fuses around 950°C instead of 2050°C. enhances the mobility of the fused mixture by acting as…
Give the chemical formula of : (i) Bauxite (ii) Cryolite (iii) Sodium aluminate
(i) Al2O3.2H2O — Bauxite (ii) Na3AlF6 — Cryolite (iii) NaAlO2— Sodium aluminate