Answer:
Only
gives spontaneous reaction.
Explanation:
A redox reaction will be spontaneous if standard reduction potential (
) of the reaction is positive. Because it leads to negative standard gibbs free energy change (
), which is a thermodynamic condition for spontaneity of a reaction.

Where
and
represents standard reduction potential of reduction half cell and standard reduction potential of oxidation half cell.
(1) Oxidation:
; 
Reduction:
; 
So, 
Hence this pair will give spontaneous reaction.
(2) Similarly as above, 
Hence this pair will give non-spontaneous reaction.
(3) Similarly as above, 
Hence this pair will give non-spontaneous reaction.
(4) Similarly as above, 
Hence this pair will give non-spontaneous reaction.
Answer:
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The Great Pacific Garbage Patch is created by deep oceans. The Marine Debris is litter that ends up in oceans or other large bodies of water.
Answer:
Catalyst speeds up the chemical reactions. Catalyst is the compound that adds to the chemical reaction so that it happen more quickly. Catalyst without being consumed in the reaction accelerates the reaction. It lowers down the activation energy of the transition state and thus accelerates the reaction.
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A. The products of the change are different from the starting
substances.
<u>Explanation:</u>
Whenever there is a physical change it may just affect the phase change but the properties remains the same. Whenever there is an occurrence of a chemical change, it was indicated by some of these things such as,
- The products are exactly different from the products.
- Chemical properties of these reactants are entirely different from that of the products.
- Chemical composition as well as the physical properties of the reactants and the products will change