Thermochemistry

The heat change can be calculated using the formula: Where m is the mass of water, c is the specific heat of water, and is the change in temperature. For the NaCl, the heat change corresponds to its heat of solution.

Using Hess's Law, we can combine the given reactions to find the heat of formation of CO (g).
The first reaction is the formation of CO from C(s) and O .
The second reaction is the formation of CO from CO(g) and O . We want to find the heat of formation of CO(g), which involves forming CO(g) from its elements (C and O ). Starting with: 1) 2) By reversing the second reaction and halving the amounts to align with the desired equation, we get: Now, we subtract the two reactions to form the desired reaction:
Thus, the correct answer is (b) -26.4 kcal.

The heat produced per mole during combustion is related to the energy released during the reaction, which is typically proportional to the number of bonds that are broken and formed.
Cyclopentane, due to its structure and the number of bonds involved, produces the most heat per mole when burned compared to the other compounds.

Thus, the correct answer is (d).

In the given reactions, carbon is shown to oxidize zinc in the second reaction.
This is evident as zinc is oxidized, which requires the presence of carbon.
Hence, carbon can oxidize zinc.