The change in standard free energy for the given reaction is 1 kJ mol at room

The change in standard free energy for the given

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The change in standard free energy for thegiven reaction is-1 kJ/mol at room tem-perature.What is the equilibrium constantfor the reaction at the same temperature?(R= 8.3 J·K1mol1) 1.0.012.1.0 0196.0 pointsConsider the reaction, The equilibrium constant,K, is 2.If theconcentrations of A, B and C are 2 M, 2 Mand 10 M, respectively, which of the followingwould occur? 020 6.0 points Which of the following gases are more solublein water when their partial pressure above thesolution is increased?
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Version 406 – Exam 1 – laude – (51635) 7 2. all of them correct 3. Cl 2 , NO 2 , SO 3 , HI 4. HI , NH 3 5. NO 2 , O 2 , HI 6. NO 2 , SO 3 Explanation: Henry’s Law states that the solubility of gases increase as their partial pressure above the solvent increases. 021 6.0 points What would be the pH of a solution of hypo- bromous acid (HOBr) prepared by dissolving 9.7 grams of the acid in 20 mL of pure wa- ter (H 2 O)? The Ka of hypobromous acid is 2 × 10 9 1. 6 2. 13 3. 4 correct 4. 1 5. 10 Explanation: 9 . 7 g HOBr × 1 mol 97 g = 0 . 1 mol HOBr 0 . 1 mol HOBr 0 . 02 L H 2 O = 5 M HOBr [H + ] = (K a · C a ) 1 / 2 = (2 × 10 9 · 5) 1 / 2 = (10 8 ) 1 / 2 = 10 4 pH = - log[H + ] = - log(10 4 ) = 4 022 6.0 points When making ice cream, salt (NaCl) is added to the water and ice mixture. The equilibrium temperature of this ice-salt water mixture is 1. less than 0 C because salt has a very low specific heat. 2. less than 0 C because the dissolved salt lowers the freezing point of the ice/water mix- ture. correct 3. greater than 0 C because salt melts ice. 4. greater than 0 C because NaCl melts at a higher temperature than water. 5. less than 0 C because salt reacts with water. 6. 0 C because it is at equilibrium. Explanation: The equilibrium temperature of a water- ice mixture is 0 C ( i.e. , the freezing point). When salt is added to the mixture, the freez- ing point ( i.e. , equilibrium temperature) is lowered. Salt does melt ice, but not by rais- ing its temperature, so don’t let that choice confuse you. Salt melts ice by lowering the freezing point. 023 6.0 points Molar Gibbs energy, G m Temperature, T vapor pure liquid solvent Referring to the graph above, and using your knowledge of Δ H solution , complete the following statement concerning boiling point elevation: Adding solute decreases the molar Gibbs energy of the liquid at all temperatures by (increasing/decreasing) the molar (en- thalpy/entropy) of the liquid. This causes
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Version 406 – Exam 1 – laude – (51635) 8 Explanation:
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