Seeking help with basic questions on solution chemistry
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120 In functional analysis, if V＜1, it indicates ( ). A. Excessive functionality B. Excessively high cost to achieve the function C. Functionality and cost are in balance D. Excessively low cost to achieve the function 126 At a certain temperature, the equilibrium total pressure for the thermal decomposition reaction NH4HCO3(s) → NH3(g) + H2O(g) + CO2(g) is 120 kPa. Then the standard equilibrium constant K for this reaction is ( ). A. 1.73 B. 0.064 C. 1.0 D. 1.20 I can’t solve these two practice questions; I’m asking experts to explain them. Thank you!
Reply to 1# bluesky991: For the first question, choose B. The cost required to achieve the function is too high; since V = F/C and this value is less than 1, it indicates high costs. For the second question, since the reactants are in solid form, their contribution can be ignored. The equilibrium constant for the remaining 3 gas-phase products is all 1; therefore, their equilibrium partial pressures equal 1/3P = 1/3*120 = 40 KPa. K = (40/P_std)³ = 0.0639, so option C should be chosen. P_std = 100 KPa
Reply to 2# Dreaming of the Prosperous Tang Dynasty: For the second question, choose B. I misread the line; the result is 0.064
Choose B for both questions. It’s not that I’m putting pressure on you – these basic concept questions are quite simple; you definitely need to know them. Hehe, good luck!
I’m ashamed; I’ve almost forgotten it too. Let’s study it a bit