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.
Answer:
Viruses cannot reproduce on their own, but inject their DNA into living cells in order to make copies of themselves.
Explanation:
A virus cannot reproduce itself outside the host because it lacks the complicated machinery that a [host] cell possesses.
<span>The purpose of the kidneys is to filter waste from the blood, and other things like water, glucose, amino acids, some minerals/vitamins, and other small molecules can also get filtered out. Reabsorbtion of water in the kidneys allows the body to maintain a fluid balance (drink a lot and you pee more cause you have an excess of water). As for the other aforementioned things, they're often needed for metabolic processes (such as certain enzyme functions) so loosing it to waste decreases efficiency and efficacy of other bodily processes. </span>
Answer:
B.
Explanation:
Glucose is an organic molecule that stores ATP or energy while Adenosine triphosphate (ATP) is an energy-carrying molecule.
ATP used as an active energy source over glucose because ATP is a shorter process and releases energy in a single reaction as glucose first converted into ATP and then used as energy in cellular respiration.
Hence, the correct option is "B".
