Answer:B) a reactant that undergoes reduction
Explanation:
Oxidation reaction is defined as the reaction in which a substance looses electrons. The oxidation state of the substance increases during oxidation.
Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation state of the substance gets reduced during reduction.

Overall reaction: 
The substance M which itself gets oxidized, reduces other and is called as reducing agent. The substance N which itself gets reduced, oxidizes other and is called as oxidizing agent.
The grey liquid is related to the white liquids because the change in colour is the result of a chemical change/reaction between the two white liquids.
The compound NaCI is an example of a salt. Salt is formed from a neutralization action of an acid and a base. From the type of reaction itself, we can say that the pH should be neutral or at pH 7.0. No matter what type of acid or base is used.
Answer:
Hydrogen Bond
Explanation:
Hydrogen bond interactions are formed between the hydrogen atom bonded to most electronegative atoms (i.e. F, O and N) of one molecule and most electronegative atom (i.e. F, O and N) of another molecule.
In this interaction the hydrogen atom has partial positive charge and electronegative atom has partial negative charge.
Answer:
D. All of these
Explanation:
The water cycle refers to how water evaporates from the surface of the earth, rises into the atmosphere, cools and condenses into rain or snow in clouds, and falls again to the surface as precipitation.
<em>Ice and glaciers are part of the water cycle, even though the water in them moves very slowly, they are considered as a form of storage but it stills evaporates into the atmosphere entering the cycle. This also applies to the ocean and surface water as they are in constant evaporation because of their exposition to the sun. </em>Therefore the correct answer is D.
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