Using the equations and enthalpy values provided, which mathematical expression can be used to determine the unknown enthalpy change represented by x?

3c + 3o2 yields 3co2 deltah = -1182 kj

4h2 + 2o2 yields 4h2o deltah =-1144 kj

c3h8 + 5o2 yields 3co2 + 4h2o deltah = x

3h8 3c + 4h2 h = 104 kj

a. 104 = (-1182) - [x + (-1144)]

b.104 = x - [(-1182) + (-1144)]

c.104 = (-1182) + (-1144) + x

d.104 = x + (-1182) - (-1144)

In order to solve this, we need to make use of Hess' Law.

We are already given the equations and their corresponding deltaH. Using Hess' Law, we can generate this equation:
104 kJ = x - (-1182 kJ) - (-1144 kJ)

Among the choices, the answer is
B.104 = x - [(-1182) + (-1144)] 

For cyclohexane compounds drawn in a chair conformation:   -axial bonds are vertical  -equatorial bonds are parallel to two bonds within the ring.  thus, as i assume the chair conformation is drawn:   -the x group is in an axial position, as are the five other vertical bonds.  -three axial bonds are on the top face of the ring  -the other three axial bonds are on the bottom face  the position of the second substituent on each ring carbon is equatorial.  gauche groups must be on an adjacent carbon such as carbon 6 and carbon 2, and also gauche groups are rotated by 60 degrees relative to each other.  drawing the newman projections for c1–c2 and c1–c6 aids in visualizing the groups that are gauche to the y group on c1.  click this link and watch some academic videos that may you more understand the topic 

No. an alpha particle is a pair of protons and a pair of neutrons, i.e. a helium