Copper coins and silver coins get a coating because of the phenomenon of corrosion. Copper coins react with carbon dioxide and moisture in the atmosphere to form copper carbonate. Silver coins react with sulphur in the atmosphere to form a coating of silver sulphide.
Copper coins and silver coins get a coating because of the phenomenon of corrosion.
Copper coins react with carbon dioxide and moisture in the atmosphere to form copper
carbonate.
Silver coins react with sulphur in the atmosphere to form a coating of silver sulphide.
Rahul has been collecting copper coins and silver coins. One day he observed a green coating on copper coins and a black coating on silver coins. State the chemical phenomenon responsible for these coatings and also write chemical names of each coating.
Copper coins and silver coins get a coating because of the phenomenon of corrosion. Copper coins react with carbon dioxide and moisture in the atmosphere to form copper carbonate. Silver coins react with sulphur in the atmosphere to form a coating of silver sulphide.
Copper coins and silver coins get a coating because of the phenomenon of corrosion.
See lessCopper coins react with carbon dioxide and moisture in the atmosphere to form copper
carbonate.
Silver coins react with sulphur in the atmosphere to form a coating of silver sulphide.
Write a balanced chemical equation to show the chemical change that occur when magnesium ribbon is burnt in air. Name the product formed and mention the characteristics of the flame produced.
2Mg (s) + O ₂ (g) ⟶ 2MgO (s) A dazzling white flame is obtained when magnedium ribbon is burnt in air
2Mg (s) + O ₂ (g) ⟶ 2MgO (s)
See lessA dazzling white flame is obtained when magnedium ribbon is burnt in air
Name any one material used to make a solar cell and also mention the range of voltage produced by a typical cell.
Silicon is most common material used to make a solar cell. A typical cell produces a voltage ranging from 0.5 to 1.0 volt.
Silicon is most common material used to make a solar cell. A typical cell produces a
See lessvoltage ranging from 0.5 to 1.0 volt.
List any two factors on which resistance of a conductor depends.
The resistance of a conductor depends on its length, its area of cross-section and the nature of its material.
The resistance of a conductor depends on its length, its area of cross-section and the nature of its material.
See lessName the hormone in humans which regulates carbohydrate, protein and fat metabolism in the body. Mention the site where it is synthesised.
The hormone that regulates carbohydrates, protein and fat metabolism in human body is thyroxine. It is synthesized by the Thyroid Gland.
The hormone that regulates carbohydrates, protein and fat metabolism in human body is thyroxine. It is synthesized by the Thyroid Gland.
See lessMarked temperature changes in aquatic environment can affect
(a) breeding of animals
(a) breeding of animals
See lessGrowth of lichens on barren rocks is followed by the growth of
(a) moss
(a) moss
See lessSoil erosion can be prevented by
(a) raising forests
(a) raising forests
See lessOxygen is harmful for
(b) nitrogen-fixing bacteria
(b) nitrogen-fixing bacteria
See lessAn increase in carbon dioxide contents in the atmosphere would not cause
(d) abundance of desert plants
(d) abundance of desert plants
See less