Answer : The entropy change for the surroundings of the reaction is, -198.3 J/K
Explanation :
We have to calculate the entropy change of reaction
.

![\Delta S^o=[n_{NH_3}\times \Delta S^0_{(NH_3)}]-[n_{N_2}\times \Delta S^0_{(N_2)}+n_{H_2}\times \Delta S^0_{(H_2)}]](https://tex.z-dn.net/?f=%5CDelta%20S%5Eo%3D%5Bn_%7BNH_3%7D%5Ctimes%20%5CDelta%20S%5E0_%7B%28NH_3%29%7D%5D-%5Bn_%7BN_2%7D%5Ctimes%20%5CDelta%20S%5E0_%7B%28N_2%29%7D%2Bn_%7BH_2%7D%5Ctimes%20%5CDelta%20S%5E0_%7B%28H_2%29%7D%5D)
where,
= entropy of reaction = ?
n = number of moles
= standard entropy of 
= standard entropy of 
= standard entropy of 
Now put all the given values in this expression, we get:
![\Delta S^o=[2mole\times (192.5J/K.mole)]-[1mole\times (191.5J/K.mole)+3mole\times (130.6J/K.mole)]](https://tex.z-dn.net/?f=%5CDelta%20S%5Eo%3D%5B2mole%5Ctimes%20%28192.5J%2FK.mole%29%5D-%5B1mole%5Ctimes%20%28191.5J%2FK.mole%29%2B3mole%5Ctimes%20%28130.6J%2FK.mole%29%5D)

Therefore, the entropy change for the surroundings of the reaction is, -198.3 J/K
Answer:
c.- How much of the reactants are needed and how much product will made.
Explanation:
The moles is the matter unit used in chemistry to simplify some calculations, instead of using grams. Also the moles are very useful because the chemical reaction can be balanced.
When a Chemical reaction is balanced, then it can be easily to calculate how many moles are necessary to add in a process to obtain a quantity of grams of a product.
LiF or lithium fluoride is the non covalent molecule or ionic compound.
Option 3.
<h3><u>Explanation:</u></h3>
Covalent molecules are those molecules which do have actual bonds between the atoms present in the molecule by sharing of the electrons. But in ionic molecules, there's no actual bonds between the atoms, but the oppositely charged ions are attracted towards each other by means of electrostatic force of attraction.
The molecules that are formed by the atoms with high electronegativity and electropositivity are actually ionic because the atoms with high electronegativity are able to actually gain electron readily and the atoms with high electropositivity are actually ready to give the electrons to the electronegative elements.
Lithium is highly electropositive and fluoride is highly electronegative. So they establish an ionic bond. But other molecules like fluorine molecule has both the electronegative elements, Carbon monoxide has carbon which isn't electropositive highly, and ammonia has hydrogen which isn't electropositive.
So lithium fluoride is the ionic compound.
Hello!
When finding the chemical formula of a compound, we will need to find the charges of each element/bond.
Looking at our period table, sodium has a +1 charge, written as Na 1+, and sulfate has a charge of -2, and it is written as SO4 2-.
Now, we need to make the charges equivalent. To do this, we need to "criss-cross" the charges. This means that sodium will need to additional atoms to make the charges equal, and sulfate will need one.
Therefore, the chemical formula for sodium sulfate is: Na2SO4.