Answer:
i) Rusting occurs the least in tubes 2 and 3 because either of air and water which are necessary for rusting is absent in the two tubes respectively.
ii) Rusting occurs most in tube 1 because both air and water which are necessary for rusting are present.
Explanation:
Rusting is a chemical change which involves a redox reaction. During the process of rusting, metallic iron is oxidized to hydrated iron (iii) oxide by oxygen present in air.
For rusting to take place effectively, each of these three factors mist be available: metallic iron, oxygen and water.
In the figure above, the iron nails in the three tester tubes will rust to different extents based on the availability of the three factors.
In test tube 1, the iron nails will rust the most because all the three factors: metallic iron, oxygen present in air, and water are abundantly present.
In test tube 2, the iron nails will rust the least or not at all because boiling of water removes dissolved oxygen from water and the oil layer above the boiled water prevents entry of oxygen from air. Thus, the nail do not rust because one of the three factors for rusting to take place, in this instance, oxygen is absent.
In test tube 3, the iron nails rusts the least or not at all as well because moisture or water is absent. Calcium chloride, a drying agent removes all the moisture from inside the tube. Hence, even though air is present, rusting do not occur as there is no moisture or water present.
The first level of organization are living cells
<span>The answer for your question is
B. A warm air mass overtakes a cold one, and the warm air gradually rises and cools. The water in the air condenses to form clouds and gentle rain.</span>
Answer:
5. Gregor Mendel
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Answer:
The correct option is lamprey.
Explanation:
Lamprey is a kind of fish which lack jaws. They lack a true skeleton, but the cartilage is present in them. Due to lack of proper backbone, they look similar to snails. The lamprey reproduces by laying eggs in the water. Larvae tend to develop from these eggs. The lamprey releases its eggs only in freshwater. Only the mature lamprey live in the sea to act as a parasite and take food. For laying eggs, it travels to freshwater.
