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A compound with a molecular formula C8H15ClO3 has the 1H NMR spectrum given. The IR spectrum shows a strong absorption at 1800 cm-1. Which of the structures shown is consistent with this spectrum?

What is the pH of the solution which results from mixing 75 mL of 0.50 M NH3(aq) and 75 mL of 0.50 HCl(aq) at 25 °C? (Kb for NH3 = 1.8 x 10–5) a. 0.60 b. 2.67 c. 4.74 d. 4.93 e. 9.26

Choose the correct table for the polynomial function   .

4. Which is the best acid to use in the preparation of a buffer with pH = 9.3? A. CH3NH2 (Kb = 3.7 × 10–4) B. NH3 (Kb = 1.8 × 10–5) C. NH2OH (Kb = 9.1 × 10–9) D. C6H5NH2 (Kb = 4.3 × 10–10)

What is the pH of a 0.28 M solution of sodium propionate, NaC3H5O2, at 25°C? (propionic acid, HC3H5O2, is monoprotic and has a Ka = 1.3 x 10–5 at 25°C.) a. 6.26 b. 7.83 c. 8.10 d. 8.74 e. 9.17

In which reaction is ΔrS° expected to be negative? a. 2C2H6(g) + 7O2(g) -> 4CO2(g) + 6H2O(l) b. Ga(l) -> Ga(s) c. H2O(l) + 2SO2(g) -> H2SO4(l) d. CO2(g) -> CO2(s) e. all of above

The standard free energy change for a chemical reaction is +13.3 kJ/mol. What is the equilibrium constant for the reaction at 125 °C?  a. 2.8 x 10–6 b. 2.0 x 10–5 c. 4.7 x 10–3 d. 3.8 x 10–2 e. 1.8 x 10-2

Find the degree of the following polynomial    .

Which of the following is correct for the condensation of gaseous water at 88°C?  The normal boiling point of water is 100°C. a. ΔH < 0, ΔS > 0, and ΔG > 0. b. ΔH < 0, ΔS < 0, and ΔG < 0. c. ΔH > 0, ΔS < 0, and ΔG < 0. d. ΔH = 0, ΔS = 0, and ΔG < 0. e. ΔH > 0, ΔS > 0, and ΔG > 0.

What is the pH of the final solution when 25 mL of 0.021 M HCl has been added to 35 mL of 0.036 M HCl at 25°C? a. 3.3 b. 1.9 c. 1.5 d. 2.7 e. 3.5