For the First-Order Reaction Below,the Initial Concentration of a Is $\mathrm{A} \rightarrow \mathrm{B}$

question 2

Multiple Choice

For the first-order reaction below,the initial concentration of A is 0.240 M.If the concentration of A decreases to 0.0800 M after 21.8 hours,what is the half-life of the reaction? $\mathrm{A} \rightarrow \mathrm{B}$$\quad$$\quad$$\quad$$\quad$$\quad$ rate $=k[\mathrm{~A}]$

• A) 0.0504 hrs
• B) 1.28 hrs
• C) 7.26 hrs
• D) 10.4 hrs
• E) 13.8 hrs

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Definitions:

Social Psychological Study

A research approach focusing on how individuals' thoughts, feelings, and behaviors are influenced by the social context and the presence of others.

Random Assignment

A research method used to assign participants to different groups in an experiment in a way that each participant has an equal chance of being placed in any group.

Independent Variable(s)

are the variables in an experiment that are manipulated to test their effect on dependent variables, allowing researchers to determine cause-and-effect relationships.

Internal Validity

The extent to which changes in the independent variable caused changes in the dependent variable.