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Which of the following statements is/are true about the graph in the previous question? Changing the concentration of A will not affect the rate of the reaction The half-life, t1/2, is independent of concentration The units for the rate constant k are s-1

Maybe useful for the following question. 

Which of the following will result in an increase in entropy? Dissolving sugar in water. Freezing of liquid water to solid ice Raising the temperature of a gas from 45.0 0C to 95.0 0C.

A 1.0 L buffer is composed of 0.225 M of formic acid (HCOOH) and 0.175 M potassium formate (KCOOH). What is the pH after the addition of 20.0 mL of 0.75 M HBr to the solution?

The standard enthalpy change (Horxn) for the reaction below was measured to be 689.0 kJ. If the standard enthalpy of formation of GeBr4 is 582.0 kJ mol-1 determine the standard enthalpy of formation of HBr. GeBr4(l) + 2H2(g) → Ge(s) + 4HBr(g)

Which of the following statements is/are true regarding buffers? HCN would be a good choice for a buffer with a desired pH of 9.50 HF would be a good choice for a buffer with a desired pH of 6.75 HIO would be a good choice for a buffer with a desired pH of 11.25

The standard enthalpy change (Horxn) for the reaction below was measured to be 672.0 kJ. If the standard enthalpy of formation of SiCl4 is 567.0 kJ mol-1 determine the standard enthalpy of formation of HCl. SiCl4(l) + 2H2(g) → Si(s) + 4HCl(g)

Which of the following statement(s) is/are correct about the fluoride ion, F-  The Kb of F- is 2.9 x 10-11 F- is the conjugate acid of HF F- hydrolyzes (reacts with water) to produce OH- ions in water.

Which of the following statements is/are true about the graph in the previous question? The half-life, t1/2, is independent of concentration Changing the concentration of A will not affect the rate of the reaction The units for the rate constant k are s-1

Which of the following statement(s) is/are incorrect (false) about a system at equilibrium              X3 (aq) + Z3 (aq) ⇌ 3 XZ (aq)                 K = 1.8 x 103 The rate of the forward reaction is equal to the rate of the reverse reaction. Both the forward and the reverse reactions stop once the system has reached equilibrium. The concentration of the products is greater than the concentration of reactants.