An indicator, HIn, shows a color change from blue to yellow, depending on the acidity of the solution:
HIn (aq) H+ (aq) + In- (aq)
(blue) (yellow)
a. blue
b. yellow
c. no color change
Answer: b. yellow
HIn (aq) H+ (aq) + In- (aq)
(blue) (yellow)
What color will the indicator change when NaOH is added?
a. blue
b. yellow
c. no color change
Answer: b. yellow
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Chemical Equilibrium
- Raising the temperature of the reaction mixture will:
- Addition of CO to an equilibrium mixture of the above reaction will
- If you mixed 5.0 mol CO2, 0.10 mol H2, 3.5 mol of CO, and 0.0010 mol H2O in a one-liter container, in which direction would the reaction proceed?
- The equilibrium constant, Kc, for the following reaction is 1.20 x 10-2 at 500K: PCl5(g) PCl3(g) + Cl2(g). Calculate Kp for this reaction.
- If an equilibrium mixture of the three gases in a 5.0L container at 298K contains 0.304mol of NOBr gas and 0.401mol of Br2 gas, what is the equilibrium concentration of NO?
- Which of the following statements is true about the above reaction?
- Dinitrogen tetraoxide exists in equilibrium with nitrogen dioxide: N2O4(g) 2NO2(g). At a certain temperature, K = 6.98 x 104. Which of the following statements is true about this reaction?
- The reaction between lead ion and chloride ion is: Pb2+(aq) + 2Cl-(aq) PbCl2(s). If K = 2.57 x 107 for this reaction, what is the value for the equilibrium constant for the reaction: 2PbCl2(s) 2Pb2+(aq) + 4Cl-(aq)?
- Which of the following is true about a chemical equilibrium?
- Kc = 2.90 x 10-2 and ΔHo = 198 kJ/mol at 1150K. Which of the following changes will favor the production of SO2?
- Calculate the equilibrium partial pressure of (CH3)2CHOH when (CH3)2CHOH is introduced into an evacuated flask at a pressure of 1.04 atm at 452K.
- A reaction mixture was found to contain 0.0381 moles of HI, 0.0471 moles of H2, and 0.0364 moles of I2 in a 1.00 L container. Is the reaction at equilibrium? And if not, what direction must it run in order to reach equilibrium?
- When she introduced 0.0683 moles of SO3 gas into a 1.00L container, she found the equilibrium concentration of O2 gas to be 0.0152 M. What is the value of the equilibrium constant, K?
- An equilibrium mixture of the three gases in a 14.1 L container at 352K contains 0.121 moles of CH2Cl2, 0.661 moles of CH4, and 0.223 moles of CCl4. What is the value of the equilibrium constant at 352K?
- The reaction: 2S(s) + 3O2(g) 2SO3(g) has an equilibrium constant of K = 1.91. What is the value of the equilibrium constant for the reaction: SO3(g) S(s) + 3/2 O2(g) ?
- For the reaction, N2O4(g) 2NO2(g), which of the following statements is true about this reaction at equilibrium?
- When the pressure of an equilibrium mixture of SO2, O2, and SO3 is doubled at constant temperature, what the effect on Kp?
- when 0.6641 L of M Tl+ is combined with 0.5864 L of M Cl− in the presence of an excess of TlCl(s)?
- Which of the following is always true for a reaction where Kc is at 25°C?
- Given the equilibrium constants for the equilibria,
- For the reaction 2NO(g) + O2(g) 2NO2(g) at 750°C, what is the relationship between Kc and Kp?
- At equilibrium, it was found that the concentration of H2 was 0.0367 M, the concentration of N2 was 0.0122 M, and the concentration of NH3 was 0.170 M. What was the initial concentration of ammonia?
- For the reaction Br2(g) + Cl2(g) 2BrCl(g), at equilibrium, it is found that the concentrations of Br2, Cl2, and BrCl are 0.277 M, 0.388 M, and M, respectively. What is the value of Kc?
- What is the balanced equation for the following equilibrium expression?