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produce carhon dioside At what temperature will this reaction be spontaneous acc

ID: 571505 • Letter: P

Question

produce carhon dioside At what temperature will this reaction be spontaneous according to Oibbr's Enery? 1According to the Second Law of Thermodynamics, the entropy of the universe must for a spontaneous process? AS in J/mol K for:CO)-1976,CO)-213.6,04) 205.0 a. increase b. remain the same c. decrease C b-temps below 179.5 K e. temps above 415.8 K d temps below 3273 K 2. Calculate G for the reaction: G in kimol for: song)--300.2, soug)--371.1 a.-70.9 b. +141.8 6. The randomness of a system may be described as its C a Gibb's energy C b. entropy c. kinetic energy C d. enthalpy C d. +70.S 7.Two 6.5 L flasks are joined by a 150 ml. tube with a stop cock. If 0.25 moles of nitrogen are held in the left flask and the right flask is empty, what happens to the entropy of the system upon opening the valve between the flasks? 3. Calculate AS for the reaction: S in Mnol K for: Nodg)-240.0, Ni(g)-191.5, 04)- 205.0 C a. The entropy remains the same. b. The entropy decreases. C. There is too little information to assess the change. a. +157 J/K b.-480 J/K c. +108 J/K C d.-157 JK d. The entropy increases 8. Without detailed calculations, predict the sign of AS for the system for 4. Consider the combustion of glucose (CH O.). This reaction is: Mg(s) + O2(g) MgO(s) a. positive (+ b. too little information to assess the change a. non-spontaneous at all temperatures b. non-spontancous towards lower temperatures c. negative () c.spontaneous at all temperatures d. spontaneous towards higher temperatures d. zero 9. All reactions with a positive AS are spontaneous

Explanation / Answer

Q1

2nd law --> states that chaos increase for spontaneous processes

therefore

entropy must INCREASE

Q2

dG = dGproducts - Greactants

dG = 2*SO2 + O2 - 2SO3

dG = (2*-300.2) -2*-371.1 = 141.8

this is endothermic

choose B

Q3

d S= Sprodc - Sreact

dS = 2N2 + O2 - 2NO2

dS = 2*191.5 + 205 - 2*240

dS = 108 J/K

Q4

combustino is spontaneous at any T, since it can oxidize at any moment