Chemistry miscellaneous
- Which of the following caused radioactive pollution along the coast of Kerala ?
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Thorium-rich monazite sand deposits on the Kerala coast has been responsible for natural radioactive contamination. It has been pronounced on the southwest coastal line of the state. The region has been found to have elevated levels of background radioactivity due to high abundance of thorium.
Correct Option: C
Thorium-rich monazite sand deposits on the Kerala coast has been responsible for natural radioactive contamination. It has been pronounced on the southwest coastal line of the state. The region has been found to have elevated levels of background radioactivity due to high abundance of thorium.
- Chernobyl disaster is the result of pollution by
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The Chernobyl disaster was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in the city of Pripyat, then located in the Ukrainian USSR. An explosion and fire released large quantities of radioactive particles into the atmosphere, which spread over much of the western USSR and Europe.
Correct Option: D
The Chernobyl disaster was a catastrophic nuclear accident that occurred on 26 April 1986 at the Chernobyl Nuclear Power Plant in the city of Pripyat, then located in the Ukrainian USSR. An explosion and fire released large quantities of radioactive particles into the atmosphere, which spread over much of the western USSR and Europe.
- Activated Charcoal is used to remove colouring matter from pure substances by
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Heating wood to a very high temperature in the absence of air makes charcoal. When it is heated to an even higher temperature, about 930°C, impurities are driven from its surface and it becomes activated charcoal, sometimes called decolorizing charcoal. This activated charcoal can remove impurities in either the gaseous or liquid state from many solutions. It does so by the process of adsorption, or by attracting these molecules to the surface.
Correct Option: C
Heating wood to a very high temperature in the absence of air makes charcoal. When it is heated to an even higher temperature, about 930°C, impurities are driven from its surface and it becomes activated charcoal, sometimes called decolorizing charcoal. This activated charcoal can remove impurities in either the gaseous or liquid state from many solutions. It does so by the process of adsorption, or by attracting these molecules to the surface.
- _____ gives hardness to stainless steel.
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Iron is alloyed with carbon lo make steel and has the effect of increasing the hardness and strength of iron. Pure iron cannot be hardened or strengthened by heat treatment but the addition of carbon enables a wide range of hardness and strength. High-carbon stainless steel contains a minimum of 0.3% carbon. The higher the carbon content, the less formable and the tougher the steel becomes.
Correct Option: C
Iron is alloyed with carbon lo make steel and has the effect of increasing the hardness and strength of iron. Pure iron cannot be hardened or strengthened by heat treatment but the addition of carbon enables a wide range of hardness and strength. High-carbon stainless steel contains a minimum of 0.3% carbon. The higher the carbon content, the less formable and the tougher the steel becomes.
- What is used in storage batteries?
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The electrodes of the cells in a storage battery consist of lead grids. The openings of the anodic grid is filled with spongy (porous) lead. The openings of the cathodic grid is filled with lead dioxide (PbO2). Dilute sulfuric acid (H2SO4) serves as the electrolyte.Lead-acid batteries, also known as lead storage batteries, can store a lot of charge and provide high current for short periods of time.
Correct Option: C
The electrodes of the cells in a storage battery consist of lead grids. The openings of the anodic grid is filled with spongy (porous) lead. The openings of the cathodic grid is filled with lead dioxide (PbO2). Dilute sulfuric acid (H2SO4) serves as the electrolyte.Lead-acid batteries, also known as lead storage batteries, can store a lot of charge and provide high current for short periods of time.