DU = 100 J is for a system that gives off 100 J of heat and ( )
A. does no work
B. does 200 J of work
C. has 100 J of work done on it
D. has 200 J of work done on it.
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Consider the given acid ionization constants. Identify the strongest conjugate base. Acid KaHNO2 (aq) 4.6 ´ 10-4HCHO2 (aq) 1.8 ´ 10-4HClO (aq) 2.9 ´ 10-8HCN (aq) 4.9 ´ 10-10
A. NO2- (aq)
B. CHO2- (aq)
ClO- (aq)
D. CN- (aq)
The decomposition of NH4HS is endothermic: NH4HS (s) ® NH3 (g) + H2S (g). Which change to an equilibrium mixture of this reaction results in the formation of more H2S? ( )
A. a decrease in the volume of the reaction vessel (at constant temperature)
B. an increase in the amount of NH4HS in the reaction vessel
C. an increase in temperature
D. all of the above
For the reaction 2A (g) ® B (g), the equilibrium constant is Kp = 0.76. A reaction mixture initially contains 2.0 atm of each gas (PA = 2.0 atm and PB = 2.0 atm). Which statement is true of the reaction mixture? ( )
A. The reaction mixture is at equilibrium.
B. The reaction mixture will proceed toward products.
C. The reaction mixture will proceed toward reactants.
D. It is not possible to determine from the information given the future direction of the reaction mixture.
Consider the reaction between NO and Cl2 to form NOCl: 2NO (g) + Cl2 (g) ® 2NOCl (g)A reaction mixture at a certain temperature initially contains only [NO] = 0.50 M and [Cl2] = 0.50 M. After the reaction comes to equilibrium, the concentration of NOCl is 0.30 M. Find the value of the equilibrium constant (Kc ) at this temperature. ( )
A. 11
B. 4.3
C. 6.4
D. 0.22