Answer:
The standard enthalpy of formation of this isomer of
is -220.1 kJ/mol.
Explanation:
The given chemical reaction is as follows.


The expression for the entropy change for the reaction is as follows.
![\Delta H^{o}_{rxn}=[8\Delta H^{o}_{f}(CO_{2}) +9\Delta H^{o}_{f}(H_{2}O)]-[\Delta H^{o}_{f}(C_{8}H_{18})+ \frac{25}{2}\Delta H^{o}_{f}(O_{2})]](https://tex.z-dn.net/?f=%5CDelta%20H%5E%7Bo%7D_%7Brxn%7D%3D%5B8%5CDelta%20H%5E%7Bo%7D_%7Bf%7D%28CO_%7B2%7D%29%20%2B9%5CDelta%20H%5E%7Bo%7D_%7Bf%7D%28H_%7B2%7DO%29%5D-%5B%5CDelta%20H%5E%7Bo%7D_%7Bf%7D%28C_%7B8%7DH_%7B18%7D%29%2B%20%5Cfrac%7B25%7D%7B2%7D%5CDelta%20H%5E%7Bo%7D_%7Bf%7D%28O_%7B2%7D%29%5D)



Substitute the all values in the entropy change expression.
![-5104.1kJ/mol=[8(-393.5)+9(-241.8)kJ/mol]-[\Delta H^{o}_{f}(C_{8}H_{18})+ \frac{25}{2}(0)kJ/mol]](https://tex.z-dn.net/?f=-5104.1kJ%2Fmol%3D%5B8%28-393.5%29%2B9%28-241.8%29kJ%2Fmol%5D-%5B%5CDelta%20H%5E%7Bo%7D_%7Bf%7D%28C_%7B8%7DH_%7B18%7D%29%2B%20%5Cfrac%7B25%7D%7B2%7D%280%29kJ%2Fmol%5D)



Therefore, The standard enthalpy of formation of this isomer of
is -220.1 kJ/mol.
To figure out the ratios of these compounds, it is important to remember that the charge of these compounds must be <em>
neutral</em>.
So in order to make them neutral, you must have specific ratios:

; This is true because they both have a charge of magnitude of 1.

; We need 3 chlorine atoms because we need to balance out the charge from the 3+ charge of aluminum - therefore since chlorine has a 1- charge, we need 3 atoms.

; The charges of the magnesium (2+) are balanced with the oxygen charge (2-).

; This is correct because if charges are like this, you must find the least common factor in order to know the ratio. The LCF is 6, therefore, for the atom with a 3+ charge, you need 2 of them, and for the atom with a 2- charge, you need 3 of them. This keeps the charge neutral.
Atomic number equals the number of protons or electrons. Atomic mass equals the number of protons and neutrons
primarily ionic include = sodium iodide( NaI) , calcium chloride ( CaCl2)
primarily covalent include - Ammonia (NH3) , Methane ( CH4) and
Glucose (C6H12O6)
Explanation
ionic bond is formed when there is complete transfer of electron between atoms. It occur between metal which donate electrons and a non metal which accept electrons.
for example in formation of CaCl2, ca donate 2 electron to 2 Cl atom, while 2 Cl atom accept the 2 electrons to form ionic bond.
Covalent bond is formed when two or more non metal form bond by sharing electrons pairs.
For example in NH3 3 pairs of electron are shared. to form covalent bond.
Answer:
XY4Z2 ----- square planar
XY5Z ------- square pyramidal
XY2Z----- bent < 120°
XY2Z3 ----- Linear
XY4Z ---- see saw
XY2Z2 ----- bent <109°
XY3Z2 ----- T shaped
XY3Z ----- Trigonal pyramidal
Explanation:
The valence shell electron pair repulsion theory ( VSEPR) gives the description of molecular geometry based on the relative number of electron pairs present in the molecule.
However, electron pairs repel each other, the repulsion between two lone pairs is greater than the repulsion between a lone pair and a bond pair which is also greater than the repulsion between two lone pairs.
The presence of lone pairs distort the bond angle and molecular geometry from the expected geometry based on VSEPR theory. Hence, in the presence of lone pairs of electron, the observed molecular geometry may be different from that predicted on the basis of the VSEPR theory, the bond angles also differ slightly or widely depending on the number of lone pairs present.
All the molecules in the question possess lone pairs, the number of electron pairs do not correspond to the observed molecular shape or geometry due to lone pair repulsion. Usually, the molecular geometry deals more with the arrangement of bonded atoms in the molecule.