How Long Does It Take for 105 Mg of Tritium ${ }_{1}^{3} \mathrm{H}$

question 26

Multiple Choice

How long does it take for 105 mg of tritium, ${ }_{1}^{3} \mathrm{H}$ ,to decay to 35.0 mg? The half-life of tritium is 12.3 yr.

• A) 12.3 yr
• B) 14.2 yr
• C) 19.5 yr
• D) 24.6 yr
• E) 36.9 yr

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Definitions:

Psychological Science

The study of mind, brain, and behavior through the systematic observation and experimentation.

Presidents

The elected heads of state in republican forms of government.

Experimental Studies

Research methods involving the manipulation of one variable to determine its effect on another variable in a controlled environment.

Wilhelm Wundt

Often regarded as the father of modern psychology, he established the first psychology laboratory in Leipzig, Germany, in 1879, emphasizing experimental methods.