Answer: b.
is positive and
is positive.
Explanation:-
As the temperature of the pack drops, the energy has been absorbed from the pack for dissolution of
in water. Thus as the energy has been absorbed in the reaction, the reaction is endothermic and the change in enthalpy i.e.
is positive.
The entropy is the measure of degree of randomness. The entropy increases when the randomness increases and the entropy decreases when the randomness decreases. When a substance dissolves in water, it dissociate into ions and hence the randomness increases thus the change in entropy i.e.
is positive.
The question is incomplete, complete question is:
Study this chemical reaction:

Then, write balanced half-reactions describing the oxidation and reduction that happen in this reaction.
Oxidation:
Reduction:
Answer:
Oxidation taking place in given reaction :

Reduction taking place in given reaction;
Explanation:
Redox reaction is defined as the reaction in which oxidation and reduction reaction occur side by side.
Oxidation reaction is defined as the chemical reaction in which an atom looses its electrons. The oxidation number of the atom gets increased during this reaction.
Reduction reaction is defined as the chemical reaction in which an atom gains electrons. The oxidation number of the atom gets reduced during this reaction.


In the given reaction, iron(II) ions are getting reduced and zinc metal is getting oxidized to zinc(II) ions.
Oxidation :

Reduction ;
Answer:
2. The metal would lose one electrons and the non metal would gain one electrons
Explanation:
An atom of a certain element reacts with the atoms of other elements in order to fullfill its outermost shell (called valence shell).
We notice the following:
- The elements in Group 1 (which are metals) have only 1 electron in their valence shell
- The elements in Group 17 (which are non-metals) have 1 vacancy (lack of electron) in their valence shell
This means that in order for both an atom of group 1 and an atom of group 17 to fullfill the valence shell, they have to:
- The atom in group 1 has to give away its only electron of the valence shell
- The atom in group 17 has to gain one electron in order to fullfill the shell
Therefore, the correct option is
2. The metal would lose one electrons and the non metal would gain one electrons
Answer:
It's because removal of electron from an atom, reduces the size of an atom.
Explanation:
When an electron is removed from an atom, it becomes an ion and in this case it will become a postive ion.
When an electron is removed from an atom, the charge balance of an atom is disturbed and positive charge increases in comparison to the negative charge. This results in increase nuclear (positive) charge which exerts greater attraction on the remaining electrons and as a result the remaining electrons are more strongly attracted by the nucleus and in this way the atomic size is decreased. Due to this increased nuclear attraction and reduced atomic size, it bcomes difficult to remove more electeon from the positively charged ion of reduced size. This is the reason that each successive ionization of electron requires a greater amount of energy.
The ionization energy has inverse relation with the size or radius of an atom. This also justifies the reason that why each successive ionization of an electron requires greater amount of energy.
Answer:4.15 is already in the hundreths place so you are good!
if it was 4.155 then you would round it to 4.16 but its NOT that so the answer IS 4.15
Explanation: