Chemistry miscellaneous
- The coating of a thin layer of zinc on steel or iron objects is known as
-
View Hint View Answer Discuss in Forum
Galvanization is the process of applying a protective zinc coating to steel or iron, in order to prevent rusting. Although galvanization can be done with electrochemical and electro-deposition processes, the most common method in current use is hot-dip galvanization, in which steel parts are submerged in a bath of molten zinc.
Correct Option: C
Galvanization is the process of applying a protective zinc coating to steel or iron, in order to prevent rusting. Although galvanization can be done with electrochemical and electro-deposition processes, the most common method in current use is hot-dip galvanization, in which steel parts are submerged in a bath of molten zinc.
- Which one of the following is used as a sowing agent in the preparation of soft drinks?
-
View Hint View Answer Discuss in Forum
Phosphoric acid was the foundation of the softdrink industry, long before Coca-Cola's popularity. Phosphoric acid is deliberately added to soft drinks to give them a sharper flavor. It also slows the growth of molds and bacteria, which would otherwise multiply.
Correct Option: A
Phosphoric acid was the foundation of the softdrink industry, long before Coca-Cola's popularity. Phosphoric acid is deliberately added to soft drinks to give them a sharper flavor. It also slows the growth of molds and bacteria, which would otherwise multiply.
- Which one of the following organic compound is used to remove stains of iron compounds?
-
View Hint View Answer Discuss in Forum
Oxalic acid is a reducing agent and its conjugate base, known as oxalate (C2O42–), is a chelating agent for metal cations. Oxalic acid's main applications include cleaning or bleaching, especially for the removal of rust, e.g. Bar Keepers Friend is an example of a household cleaner containing oxalic acid. Its utility in rust removal agents is due to its forming a stable, water soluble salt with ferric iron, ferrioxalate ion.
Correct Option: A
Oxalic acid is a reducing agent and its conjugate base, known as oxalate (C2O42–), is a chelating agent for metal cations. Oxalic acid's main applications include cleaning or bleaching, especially for the removal of rust, e.g. Bar Keepers Friend is an example of a household cleaner containing oxalic acid. Its utility in rust removal agents is due to its forming a stable, water soluble salt with ferric iron, ferrioxalate ion.
- Stainless steel is usually made by alloying the steel with
-
View Hint View Answer Discuss in Forum
In metallurgy, stainless steel is defined as a steel alloy with a minimum of 10.5 per cent to 11 per cent chromium content by mass. There are different types of stainless steels: when nickel is added, for instance, the austenite structure of iron is stabilized. This crystal structure makes such steels virtually non-magnetic and less brittle at low temperatures. For greater hardness and strength, more carbon is added.
Correct Option: C
In metallurgy, stainless steel is defined as a steel alloy with a minimum of 10.5 per cent to 11 per cent chromium content by mass. There are different types of stainless steels: when nickel is added, for instance, the austenite structure of iron is stabilized. This crystal structure makes such steels virtually non-magnetic and less brittle at low temperatures. For greater hardness and strength, more carbon is added.
- Which one of the following statements is not correct? Vulcanisation of rubber makes it
-
View Hint View Answer Discuss in Forum
In order to give more strength and more elasticity, natural rubber is heated with sulphur or sulphur compounds at 150°C temperature. Vulcanized rubber has good tensile strength. The working temperature of vulcanized rubber is enhanced up to 100°C. It has good resistance to organic solvents.
Correct Option: A
In order to give more strength and more elasticity, natural rubber is heated with sulphur or sulphur compounds at 150°C temperature. Vulcanized rubber has good tensile strength. The working temperature of vulcanized rubber is enhanced up to 100°C. It has good resistance to organic solvents.