The answer is B or the second answer
Answer: The heat required is 6.88 kJ.
Explanation:
The conversions involved in this process are :
Now we have to calculate the enthalpy change.
![\Delta H=[m\times c_{p,s}\times (T_{final}-T_{initial})]+n\times \Delta H_{fusion}+[m\times c_{p,l}\times (T_{final}-T_{initial})]+n\times \Delta H_{vap}+[m\times c_{p,g}\times (T_{final}-T_{initial})]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5Bm%5Ctimes%20c_%7Bp%2Cs%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D%2Bn%5Ctimes%20%5CDelta%20H_%7Bfusion%7D%2B%5Bm%5Ctimes%20c_%7Bp%2Cl%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D%2Bn%5Ctimes%20%5CDelta%20H_%7Bvap%7D%2B%5Bm%5Ctimes%20c_%7Bp%2Cg%7D%5Ctimes%20%28T_%7Bfinal%7D-T_%7Binitial%7D%29%5D)
where,
= enthalpy change = ?
m = mass of ethanol = 25.0 g
= specific heat of solid ethanol= 0.97 J/gK
= specific heat of liquid ethanol = 2.31 J/gK
n = number of moles of ethanol = 
= enthalpy change for fusion = 5.02 KJ/mole = 5020 J/mole
= change in temperature
The value of change in temperature always same in Kelvin and degree Celsius.
Now put all the given values in the above expression, we get
![\Delta H=[25.0 g\times 0.97J/gK\times (-114-(-135)K]+0.534mole\times 5020J/mole+[25.0g\times 2.31J/gK\times (-50-(-114))K]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B25.0%20g%5Ctimes%200.97J%2FgK%5Ctimes%20%28-114-%28-135%29K%5D%2B0.534mole%5Ctimes%205020J%2Fmole%2B%5B25.0g%5Ctimes%202.31J%2FgK%5Ctimes%20%28-50-%28-114%29%29K%5D)
(1 KJ = 1000 J)
Therefore, the heat required is 6.88 kJ
The final product cannot be converted back to the original ingredients. This is why baking a chocolate chip cookie is a chemical reaction.
C) H2O has the strongest dipole interactions
Explanation:
The dipole interactions are the interactions that occur between polar molecules.
Polar molecules form when the atoms forming the molecule have different electronegativity, therefore one of the atom in the molecule attract the shared electrons more towards itself; as a result, the molecule ends up having a region which is slightly negatively charged and a region slightly positively charged.
In this problem, we are comparing 4 different molecules. We observe that:
H2: this molecule is formed by 2 atoms of hydrogen - since the two atoms are identical, electrons are equally shared between the two atoms, so this molecule is not polar
O2: this molecule is formed by 2 identical atoms of oxygen, so it is not polar, for the same reason as H2
CH4: this molecule consists of a carbon atom surrounded by 4 hydrogen atoms - since this molecule has a symmetric structure, the charge is balanced, therefore this molecule is not polar
H2O (water): the oxygen atom in the water molecule is more electronegative than the hydrogens, therefore it tends to attract more the shared electrons - as a result, the molecule is polar.
Therefore, the correct answer is H2O.
Learn more about atoms and molecules:
brainly.com/question/2757829
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