Which equation is used to determine the amount of time required for the initial concentration to decrease by 45% if the rate constant has units of s⁻¹?

A reaction has a rate law of Rate = (1.25 M⁻²s⁻¹)[A][B]². What concentration of [B] would give the reaction a rate of 0.0891 M/s if the concentration of [A] is 0.250 M?

A reaction was shown to follow second-order kinetics. How much time is required for [A] to change from 0.500 M to 0.250 M? (k = 0.456 M⁻¹ s⁻¹)

The radioisotope ¹⁴C (half life = 5730 years) is used for carbon dating. What is the first order rate constant for ¹⁴C?

Match the slope of each line to the average, initial, or instantaneous reaction rate.

Considering the rate law, rate = k[A]²[B], which of the following statements is correct? A B C D E Add

Which species has the greatest rate of disappearance in the reaction below? CH₄ + 2 O₂ → CO₂ + 2 H₂O

Consider BrF5 molecule.  1) Use your own words, describe how chemical bonds are formed in Valence Bond Theory between Br and F atoms? 2) What’s the molecular geometry of the molecule (molecular geometry only)? Explain how you get your conclusion. Mark your answer next to words “Final answer is”.

Determine the enthalpy of reaction of the following equation using Hess’s Law.                           FeS2 +  5/2 O2      FeO  +  2 SO2 Given the following experimental data:  Fe + 2 S       FeS2   ∆H1 = -178.2 KJ/mol  ∆H2 = -272.0 kJ/mol ∆H3 = -296.8 kJ/mol   Mark your answer next to words “Final answer is”. You must follow significant figure rules.  Show your work here to receive full credit.  

12 month old Maggie’s mother has a friend whose 12 month old already has 15 words.  She asks if you think Maggie is a “late talker.”  You explain the characteristics of a late talker : (select all that apply)