The thermochemical equation for the formation of ammonia from elemental nitrogen and hydrogen is as follows.   N2(g) + 3 H2(g) 2 NH3(g) ΔH = –92.2 kJ Given a system that is initially at equilibrium, which of the following actions cause the reaction to proceed to the left?

Nitrogen and oxygen gases may react to form nitrogen monoxide. At 1500 °C, Kc equals 1.0 × 10−5.   N2(g) + O2(g) 2 NO(g)   If 0.030 mol N2 and 0.030 mol O2 are sealed in a 1.0 L flask at 1500 °C, what is the concentration of NO(g) when equilibrium is established?

The equilibrium constant (Kc) for the decomposition of ammonium hydrogen sulfide, NH4HS(s)  NH3(g) + H2S(g), is 1.8 × 10–4 at 25 °C. If excess NH4HS(s) is allowed to equilibrate at 25 °C, what is the equilibrium concentration of NH3?

A second-order reaction starts with an initial concentration of 0.100 mol/L of the reactant. If the rate constant is 2.6 × 10–2 L/mol·s, what is the time required to decrease the initial concentration to 0.050 mol/L?   2A → B rate = k[A]2  

For the reaction given below, 2.00 moles of A and 3.00 moles of B are placed in a 6.00-L container. A(g) + 2B(g)  C(g) At equilibrium, the concentration of A is 0.230 mol/L. What is the value of Kc?

The reaction kinetics for a certain reaction are studied over several temperatures. Which of the following is/are not effected by a change in reaction temperature?

At 800 K, the equilibrium constant, Kp, for the following reaction is 3.2 × 10–7. 2 H2S(g) 2 H2(g) + S2(g) A reaction vessel at 800 K initially contains 3.00 atm of H2S. If the reaction is allowed to equilibrate, what is the equilibrium pressure of S2?

Excess Ag2SO4(s) is placed in water at 25 °C. At equilibrium, the solution contains 0.029 M Ag+(aq). What is the equilibrium constant for the reaction below? Ag2SO4(s) 2 Ag+(aq) + SO42–(aq)

A mixture of nitrogen and hydrogen was allowed to come to equilibrium at a given temperature. 3H2 + N2    2NH3 An analysis of the mixture at equilibrium revealed 2.1 mol N2, 2.8 mol H2, and 1.8 mol NH3. How many moles of H2 were present at the beginning of the reaction?

What is the name given to a substance that increases the rate of a chemical reaction but is not itself consumed?