Question

Butane combusts in the atmosphere and releases heat:2C4H10(g) + 13 O2(g) ----> 8 CO2(g) + 10 H2O(g)The signs of the values for ΔG, ΔH, and ΔS for this reaction would be-, +, +-, -, ++, -, -+, +, -

Answer 1

-,-,+

Step-by-step explanation:

The free-energy (ΔG) is the measure of the spontaneously of a reaction. When a reaction is spontaneous, ΔG < 0. All combustion reactions are spontaneous because when it beggings, it will happen until the combustible or the oxygen ends. So, the signal for ΔG for the reaction is "-".

The change in enthalpy (ΔH) is the measure of the energy in the system, in the form of heat. When a reaction absorbs heat, it's enthalpy increases, so ΔH>0, and the reaction is endothermic. When the system releases heat, the enthalpy decreases, so ΔH < 0 and the reaction are exothermic. All combustion reaction releases heat. Then, the signal of ΔH is "-".

The change in entropy (ΔS) is the measure of the randomness of the system. When the randomness increases, ΔS > 0. When an irreversible reaction is taking place, it indicates that the randomness is increasing, because all the systems intend for an increase in the randomness. So, the combustion reaction has the signal of ΔS "+".