Answer: C. Electrochemical cells involve oxidation-reduction reactions.
Explanation: Oxidation occurs at the anode, and reduction occurs at the cathode.
Answer: Oxidation reaction: 
Reduction reaction: 
Overall redox reaction : 
Explanation:
Oxidation-reduction reaction or redox reaction is defined as the reaction in which oxidation and reduction reactions occur simultaneously.
Oxidation reaction is defined as the reaction in which a substance looses its electrons. The oxidation state of the substance increases.

Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation state of the substance gets reduced.

Overall redox reaction : 
<u>Answer:</u> The correct answer is Option E.
<u>Explanation:</u>
Every balanced chemical equation follows law of conservation of mass.
This law states that mass can neither be created nor be destroyed but it can only be transformed from one form to another form.
This also means that total mass on the reactant side must be equal to the total mass on the product side.
The balanced chemical equation for the reaction of aluminium and water follows:

The coefficient of Aluminium is 2.
Hence, the correct answer is Option E.
RbOH + HBr = RbBr + H₂O
NaOH + HClO₄ = NaClO₄ + H₂O
rubidium bromide RbBr and sodium perchlorate NaClO₄ are formed by the strong basis and the strong acid
pH=7
Answer:
cooperation for the first, then predation, the last is competition.
Explanation:
i got it right. hope it helps!