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.
Answer:
pineal body is a vastigious structure which signifies same origin of chimpanzee and modern man
Explanation:
Roman numerals are used in naming ionic compounds when the metal cation forms more than one ion. The metals that form more than one ion are the transition metals, although not all of them do this.
SnBr2 - Tin(II) Bromide
Answer:

Explanation:
<u>According to Arrhenius concept of acid and base:</u>
"When a base in a solution, produces/yields OH- (Hydroxide) ions."
So, when a base is dissolved in a solution, it produces OH- ions.
<u>For example:</u>
NaOH ⇄ Na⁺ + OH⁻ (So, it is a base)
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Hope this helped!
<h3>~AH1807</h3>
C burning coal in a furnace