Answer:
The correct answer is B. It is spontaneous only at low temperatures.
Explanation:
In thermodynamics, the Gibbs free energy is a thermodynamic potential that can be used to calculate the maximum of reversible work that may be performed by a thermodynamic system at a constant temperature and pressure.
The spontaneity of a reaction is given by the equation:
ΔG = ΔH - TΔS
where:
ΔH: enthalpy variation
T: absolute temperature
ΔS: entropy variation
As the reaction is exothermic, ΔH<0
As the reaction order increases (the reagents are solid and gas and their product is solid), ΔS<0
Therefore, the reaction will be spontaneous when ΔG is negative.
ΔG = ΔH - TΔS
That is, the entropy term must be smaller than the enthalpy term.
Hence, the reaction will be spontaneous only at low temperatures.
All of the energy from the Sun that reaches the Earth arrives as solar radiation, part of a large collection of energy called the electromagnetic radiation spectrum. Solar radiation includes visible light, ultraviolet light, infrared, radio waves, X-rays, and gamma rays. Radiation is one way to transfer heat.
Answer:
a) decrease, gas
b) increase, gas
c) liquid
d) increase, solid
Explanation:
Entropy refers to the degree of disorderliness of a system. If the number of moles of gas increases from left to right in a reaction, the entropy of the system increases positively.
Similarly, when the number of liquid molecules remain constant, there could only be a very little increase in entropy.
However, solids have the least entropy and the entropy of a system decreases when a system yields solid products.
Answer:
Option (C) 4.5 liters
Explanation:
1mole of a gas occupy 22.4L at stp.
This implies that 1mole of He also occupy 22.4L at stp.
From the question given, we were asked to find the volume occupied by 0.20 mole of He at STP. This can be achieved by doing the following:
1mole of He occupied 22.4L.
Therefore, 0.2mol of He will occupy = 0.2 x 22.4L = 4.48 = 4.5L
♥ In fact, the similarity of the numbers 85,19,17,4&2 is <span>that they are all divisors of 6460.
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