Answer:
1. d. The reaction is spontaneous in the reverse direction at all temperatures.
2. c. The reaction is spontaneous at low temperatures.
Explanation:
The spontaneity of a reaction is associated with the Gibbs free energy (ΔG). When ΔG < 0, the reaction is spontaneous. When ΔG > 0, the reaction is non-spontaneous. ΔG is related to the enthalpy (ΔH) and the entropy (ΔS) through the following expression:
ΔG = ΔH - T. ΔS [1]
where,
T is the absolute temperature (T is always positive)
<em>1. What can be said about an Endothermic reaction with a negative entropy change?</em>
If the reaction is endothermic, ΔH > 0. Let's consider ΔS < 0. According to eq. [1], ΔG is always positive. The reaction is not spontaneous in the forward direction at any temperature. This means that the reaction is spontaneous in the reverse direction at all temperatures.
<em>2. What can be said about an Exothermic reaction with a negative entropy change?</em>
If the reaction is exothermic, ΔH < 0. Let's consider ΔS < 0. According to eq. [1], ΔG will be negative when |ΔH| > |T.ΔS|, that is, at low temperatures.
Convert amount of molecules into moles using Avogadro’s number
9.40 x 10^25 molecules H2 x 1 mole / 6.02 x 10^23 molecules
= 156 moles H2
Convert moles of H2 into grams using H2’s molar mass (1.01 x 2 = 2.02)
156 mol H2 x 2.02 g / 1 mol
= 315 g H2
Answer:
162.2 g/mol
Explanation:
Molar mass is defined as the mass in 1 mole of the substance. It is calculated by adding the molar mass of the substituents each multiplied by the subscript they have in the formula.
Thus, To calculate molar mass of nicotine having formula, 
Molar mass of C = 12.0107 g/mol
Molar mass of H = 1.00784 g/mol
Molar mass of N = 14.0067 g/mol
Thus, molar mass of nicotine = 
= 162.2 g/mol
Answer:
Nuclear fission power plants have the disadvantage of generating unstable nuclei; some of these are radioactive for millions of years. Fusion on the other hand does not create any long-lived radioactive nuclear waste. A fusion reactor produces helium, which is an inert gas.
