An exponential decay law has the general form: A = Ao * e ^ (-kt) =>
A/Ao = e^(-kt)
Half-life time => A/Ao = 1/2, and t = 4.5 min
=> 1/2 = e^(-k*4.5) => ln(2) = 4.5k => k = ln(2) / 4.5 ≈ 0.154
Now replace the value of k, Ao = 28g and t = 7 min to find how many grams of Thalium-207 will remain:
A = Ao e ^ (-kt) = 28 g * e ^( -0.154 * 7) = 9.5 g
Answer 9.5 g.
When 6.85×10⁵ cal is converted to kilojoules, the result obtained is 2866.04 KJ
<h3>Data obtained from the question </h3>
- Energy (cal) = 6.85×10⁵ cal
- Energy (KJ) =?
<h3>Conversion scale </h3>
1 cal = 0.004184 KJ
<h3>How to convert 6.85×10⁵ cal to kilojoules</h3>
1 cal = 0.004184 KJ
Therefore,
6.85×10⁵ cal = 6.85×10⁵ × 0.004184
6.85×10⁵ cal = 2866.04 KJ
Thus, 6.85×10⁵ cal is equivalent to 2866.04 KJ
Learn more about conversion:
brainly.com/question/2139943
Answer:
violet
Explanation:
Waves with a short wavelength have the most energy. Red waves have a relatively long wavelength (in the 700 nm range), and violet waves are much shorter - roughly half that. Because violet waves have the shortest wavelength of the visible light spectrum, they carry the most energy (google)
Acids or bases<span> with weak bonds easily dissociate into ions and are called "</span>strong<span>" acids or </span>bases<span>. Table 1: Summary List of </span>Characteristics<span> for </span>Strong<span> and Weak Acids and </span>Bases<span>. All </span>characteristics<span> of acids and </span>bases<span> are related to whether the predominate forms are molecules and ions. </span>Characteristic<span>.</span>